0001692115-22-000035 | 10-Q | XBRL Viewer | Southwest GAS Holdings INC

Cover - shares	9 Months Ended
Cover - shares	Sep. 30, 2022	Oct. 31, 2022
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2022
Document Transition Report	false
Entity File Number	001-37976
Entity Registrant Name	Southwest Gas Holdings, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	81-3881866
Entity Address, Address Line One	8360 S. Durango Drive
Entity Address, Address Line Two	Post Office Box 98510
Entity Address, City or Town	Las Vegas,
Entity Address, State or Province	NV
Entity Address, Postal Zip Code	89193-8510
City Area Code	(702)
Local Phone Number	876-7237
Title of 12(b) Security	Southwest Gas Holdings, Inc. Common Stock, $1 Par Value
Trading Symbol	SWX
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		67,067,822
Entity Central Index Key	0001692115
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q3
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Southwest Gas Corporation
Entity Information [Line Items]
Document Type	10-Q
Entity File Number	1-7850
Entity Registrant Name	Southwest Gas Corporation
Entity Incorporation, State or Country Code	CA
Entity Tax Identification Number	88-0085720
Entity Address, Address Line One	8360 S. Durango Drive
Entity Address, Address Line Two	Post Office Box 98510
Entity Address, City or Town	Las Vegas,
Entity Address, State or Province	NV
Entity Address, Postal Zip Code	89193-8510
City Area Code	(702)
Local Phone Number	876-7237
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Central Index Key	0000092416
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q3
Amendment Flag	false
Current Fiscal Year End Date	--12-31

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Regulated operations plant:
Gas plant	$ 11,166,691	$ 10,789,690
Less: accumulated depreciation	(3,536,274)	(3,397,736)
Construction work in progress	273,662	202,068
Net regulated operations plant	7,904,079	7,594,022
Other property and investments, net	1,311,334	1,316,479
Current assets:
Cash and cash equivalents	175,272	222,697
Accounts receivable, net of allowance	779,558	707,127
Accrued utility revenue	41,300	84,900
Income taxes receivable, net	15,580	16,816
Deferred purchased gas costs	381,351	291,145
Prepaid and other current assets	316,578	292,082
Total current assets	1,709,639	1,614,767
Noncurrent assets:
Goodwill	1,742,967	1,781,332
Deferred income taxes	322	121
Deferred charges and other assets	434,236	458,536
Total noncurrent assets	2,177,525	2,239,989
Total assets	13,102,577	12,765,257
Capitalization:
Common stock, $1 par (authorized - 120,000,000 shares; issued and outstanding - 67,063,730 and 60,422,081 shares)	68,694	62,052
Additional paid-in capital	2,283,250	1,824,216
Accumulated other comprehensive loss, net	(50,232)	(46,761)
Retained earnings	1,111,203	1,114,313
Total equity	3,412,915	2,953,820
Redeemable noncontrolling interests	114,692	196,717
Long-term debt, less current maturities	5,865,591	4,115,684
Total capitalization	9,393,198	7,266,221
Current liabilities:
Current maturities of long-term debt	41,485	297,324
Short-term debt	381,000	1,909,000
Accounts payable	308,824	353,365
Customer deposits	55,033	59,327
Income taxes payable, net	4,516	6,734
Accrued general taxes	72,941	53,473
Accrued interest	41,484	30,964
Deferred purchased gas costs	3,742	5,736
Other current liabilities	404,703	396,126
Total current liabilities	1,313,728	3,112,049
Deferred income taxes and other credits:
Deferred income taxes and investment tax credits, net	774,465	768,868
Accumulated removal costs	500,052	480,583
Other deferred credits and other long-term liabilities	1,121,134	1,137,536
Total deferred income taxes and other credits	2,395,651	2,386,987
Total capitalization and liabilities	$ 13,102,577	$ 12,765,257

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Common stock, par (in USD per share)	$ 1	$ 1
Common stock, authorized (in shares)	120,000,000	120,000,000
Common stock, issued (in shares)	67,063,730	60,422,081
Common stock, outstanding (in shares)	67,063,730	60,422,081

CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Operating revenues:
Regulated operations revenues	$ 367,122	$ 255,848	$ 1,550,684	$ 1,070,576	$ 2,001,898	$ 1,445,066
Utility infrastructure services revenues	758,466	632,848	1,988,433	1,525,448	2,621,646	2,065,038
Total operating revenues	1,125,588	888,696	3,539,117	2,596,024	4,623,544	3,510,104
Operating expenses:
Net cost of gas sold	100,991	63,710	547,769	296,227	682,449	374,449
Operations and maintenance	154,236	122,927	479,330	334,450	618,026	437,602
Depreciation and amortization	116,933	91,380	347,589	267,670	450,960	354,688
Taxes other than income taxes	23,356	20,109	70,778	60,134	90,987	76,087
Utility infrastructure services expenses	680,135	567,270	1,829,560	1,381,524	2,403,503	1,858,464
Total operating expenses	1,075,651	865,396	3,275,026	2,340,005	4,245,925	3,101,290
Operating income (loss)	49,937	23,300	264,091	256,019	377,619	408,814
Other income and (expenses):
Net interest deductions	(64,373)	(31,298)	(165,942)	(81,201)	(203,939)	(109,537)
Other income (deductions)	1,593	(3,112)	2	(3,975)	478	282
Total other income and (expenses)	(62,780)	(34,410)	(165,940)	(85,176)	(203,461)	(109,255)
Income (loss) before income taxes	(12,843)	(11,110)	98,151	170,843	174,158	299,559
Income tax expense (benefit)	(1,525)	(1,816)	18,300	34,818	23,130	58,498
Net income (loss)	(11,318)	(9,294)	79,851	136,025	151,028	241,061
Net income attributable to noncontrolling interests	991	2,282	2,557	5,189	3,791	6,681
Net income (loss) attributable to Southwest Gas Holdings, Inc.	$ (12,309)	$ (11,576)	$ 77,294	$ 130,836	$ 147,237	$ 234,380
Earnings (loss) per share:
Basic (in USD per share)	$ (0.18)	$ (0.19)	$ 1.19	$ 2.23	$ 2.30	$ 4.03
Diluted (in USD per share)	$ (0.18)	$ (0.19)	$ 1.19	$ 2.23	$ 2.30	$ 4.02
Weighted average shares:
Basic (in shares)	67,157	59,688	65,004	58,639	63,905	58,209
Diluted (in shares)	67,325	59,816	65,148	58,742	64,051	58,312

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (11,318)	$ (9,294)	$ 79,851	$ 136,025	$ 151,028	$ 241,061
Defined benefit pension plans:
Net actuarial gain (loss)	0	0	0	0	44,974	(43,730)
Amortization of prior service cost	34	183	100	547	282	766
Amortization of net actuarial loss	6,616	8,474	19,847	25,420	28,321	32,608
Regulatory adjustment	(5,524)	(7,277)	(16,571)	(21,831)	(61,767)	2,959
Net defined benefit pension plans	1,126	1,380	3,376	4,136	11,810	(7,397)
Forward-starting interest rate swaps (“FSIRS”):
Amounts reclassified into net income (loss)	0	413	416	1,240	828	1,653
Net forward-starting interest rate swaps	0	413	416	1,240	828	1,653
Foreign currency translation adjustments	(5,830)	(2,056)	(7,263)	(324)	(6,919)	2,576
Total other comprehensive income (loss), net of tax	(4,704)	(263)	(3,471)	5,052	5,719	(3,168)
Comprehensive income (loss)	(16,022)	(9,557)	76,380	141,077	156,747	237,893
Comprehensive income attributable to noncontrolling interests	991	2,282	2,557	5,189	3,791	6,681
Comprehensive income (loss) attributable to Southwest Gas Holdings, Inc.	$ (17,013)	$ (11,839)	$ 73,823	$ 135,888	$ 152,956	$ 231,212

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
CASH FLOW FROM OPERATING ACTIVITIES:
Net income	$ 79,851	$ 136,025	$ 151,028	$ 241,061
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	347,589	267,670	450,960	354,688
Deferred income taxes	22,955	45,374	38,793	58,339
Changes in current assets and liabilities:
Accounts receivable, net of allowances	(78,719)	(62,081)	(68,192)	(68,714)
Accrued utility revenue	43,600	42,700	(1,600)	(3,200)
Deferred purchased gas costs	(92,200)	(293,410)	(142,518)	(317,070)
Accounts payable	(29,353)	(51,086)	72,159	251
Accrued taxes	18,352	5,954	5,673	3,134
Other current assets and liabilities	(1,039)	23,289	(113,537)	9,531
Gains on sale of property and equipment	(5,215)	(5,365)	(6,756)	(6,632)
Changes in undistributed stock compensation	7,855	7,676	9,473	9,001
Equity AFUDC	(912)	0	(912)	(1,311)
Changes in deferred charges and other assets	16,417	(7,956)	10,832	(21,373)
Changes in other liabilities and deferred credits	(25,826)	(57,269)	(42,186)	(67,922)
Net cash provided by operating activities	303,355	51,521	363,217	189,783
CASH FLOW FROM INVESTING ACTIVITIES:
Construction expenditures and property additions	(612,516)	(506,737)	(821,405)	(699,368)
Acquisition of businesses, net of cash acquired	(18,809)	(830,395)	(1,542,674)	(830,145)
Changes in customer advances	23,222	7,940	31,256	14,282
Other	4,005	14,755	7,506	17,238
Net cash used in investing activities	(604,098)	(1,314,437)	(2,325,317)	(1,497,993)
CASH FLOW FROM FINANCING ACTIVITIES:
Issuance of common stock, net	459,051	210,812	461,880	259,422
Centuri distribution to redeemable noncontrolling interest	(39,649)	0	(39,649)	0
Dividends paid	(118,980)	(102,292)	(154,910)	(134,479)
Issuance of long-term debt, net	770,240	1,654,960	775,976	1,666,718
Retirement of long-term debt	(422,356)	(406,815)	(468,205)	(473,926)
Change in credit facility and commercial paper	8,000	(150,000)	138,000	(58,000)
Change in short-term debt	(380,253)	165,000	(593,253)	218,000
Issuance of short-term debt	0	0	1,850,000	0
Withholding remittance - share-based compensation	(2,105)	(1,254)	(2,115)	(1,254)
Other	(19,929)	(4,355)	(16,303)	(6,161)
Net cash provided by financing activities	254,019	1,366,056	1,951,421	1,470,320
Effects of currency translation on cash and cash equivalents	(701)	198	(739)	635
Change in cash and cash equivalents	(47,425)	103,338	(11,418)	162,745
Cash and cash equivalents at beginning of period	222,697	83,352	186,690	23,945
Cash and cash equivalents at end of period	175,272	186,690	175,272	186,690
SUPPLEMENTAL INFORMATION:
Interest paid, net of amounts capitalized	146,792	57,128	194,016	98,567
Income taxes paid, net	$ 10,317	$ 7,665	$ 6,860	$ 12,720

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total	Common stock shares	Additional paid-in capital	Accumulated other comprehensive loss	Retained earnings	Southwest Gas Holdings, Inc.
Beginning balance (in shares) at Dec. 31, 2020		57,193,000
Beginning balance at Dec. 31, 2020		$ 58,823	$ 1,609,155	$ (61,003)	$ 1,067,978
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issuances (in shares)		3,186,000
Common stock issuances		$ 3,186	214,734
Foreign currency exchange translation adjustment				(324)
Net actuarial gain arising during period, less amortization of unamortized benefit plan cost, net of tax				4,136
FSIRS amounts reclassified to net income, net of tax	$ 1,240			1,240
Net income (loss)					130,836
Dividends declared					(106,303)
Redemption value adjustments					(12,642)
Ending balance (in shares) at Sep. 30, 2021		60,379,000
Ending balance at Sep. 30, 2021		$ 62,009	1,823,889	(55,951)	1,079,869	$ 2,909,816
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared per share (in USD per share)	$ 1.785
Beginning balance (in shares) at Jun. 30, 2021		59,088,000
Beginning balance at Jun. 30, 2021		$ 60,718	1,733,572	(55,688)	1,108,279
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issuances (in shares)		1,291,000
Common stock issuances		$ 1,291	90,317
Foreign currency exchange translation adjustment				(2,056)
Net actuarial gain arising during period, less amortization of unamortized benefit plan cost, net of tax				1,380
FSIRS amounts reclassified to net income, net of tax	$ 413			413
Net income (loss)					(11,576)
Dividends declared					(36,098)
Redemption value adjustments					19,264
Ending balance (in shares) at Sep. 30, 2021		60,379,000
Ending balance at Sep. 30, 2021		$ 62,009	1,823,889	(55,951)	1,079,869	2,909,816
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared per share (in USD per share)	$ 0.595
FSIRS amounts reclassified to net income, net of tax	$ 828
Ending balance (in shares) at Sep. 30, 2022	67,063,730	67,064,000
Ending balance at Sep. 30, 2022		$ 68,694	2,283,250	(50,232)	1,111,203	3,412,915
Beginning balance (in shares) at Dec. 31, 2021	60,422,081	60,422,000
Beginning balance at Dec. 31, 2021		$ 62,052	1,824,216	(46,761)	1,114,313
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issuances (in shares)		6,642,000
Common stock issuances		$ 6,642	459,034
Foreign currency exchange translation adjustment				(7,263)
Net actuarial gain arising during period, less amortization of unamortized benefit plan cost, net of tax				3,376
FSIRS amounts reclassified to net income, net of tax	$ 416			416
Net income (loss)					77,294
Dividends declared					(125,337)
Redemption value adjustments	$ (44,933)				44,933
Ending balance (in shares) at Sep. 30, 2022	67,063,730	67,064,000
Ending balance at Sep. 30, 2022		$ 68,694	2,283,250	(50,232)	1,111,203	3,412,915
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared per share (in USD per share)	$ 1.86
Beginning balance (in shares) at Jun. 30, 2022		67,004,000
Beginning balance at Jun. 30, 2022		$ 68,634	2,279,493	(45,528)	1,156,253
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issuances (in shares)		60,000
Common stock issuances		$ 60	3,757
Foreign currency exchange translation adjustment				(5,830)
Net actuarial gain arising during period, less amortization of unamortized benefit plan cost, net of tax				1,126
FSIRS amounts reclassified to net income, net of tax	$ 0			0
Net income (loss)					(12,309)
Dividends declared					(41,696)
Redemption value adjustments					8,955
Ending balance (in shares) at Sep. 30, 2022	67,063,730	67,064,000
Ending balance at Sep. 30, 2022		$ 68,694	$ 2,283,250	$ (50,232)	$ 1,111,203	$ 3,412,915
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared per share (in USD per share)	$ 0.62

CONDENSED CONSOLIDATED BALANCE SHEETS - Southwest - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
ASSETS
Gas plant	$ 11,166,691	$ 10,789,690
Less: accumulated depreciation	(3,536,274)	(3,397,736)
Construction work in progress	273,662	202,068
Net regulated operations plant	7,904,079	7,594,022
Other property and investments, net	1,311,334	1,316,479
Current assets:
Cash and cash equivalents	175,272	222,697
Accounts receivable, net of allowance	779,558	707,127
Accrued utility revenue	41,300	84,900
Income taxes receivable, net	15,580	16,816
Deferred purchased gas costs	381,351	291,145
Prepaid and other current assets	316,578	292,082
Total current assets	1,709,639	1,614,767
Noncurrent assets:
Goodwill	1,742,967	1,781,332
Deferred charges and other assets	434,236	458,536
Total noncurrent assets	2,177,525	2,239,989
Total assets	13,102,577	12,765,257
Capitalization:
Common stock	68,694	62,052
Additional paid-in capital	2,283,250	1,824,216
Accumulated other comprehensive loss, net	(50,232)	(46,761)
Retained earnings	1,111,203	1,114,313
Total equity	3,412,915	2,953,820
Long-term debt, less current maturities	5,865,591	4,115,684
Total capitalization	9,393,198	7,266,221
Current liabilities:
Current maturities of long-term debt	41,485	297,324
Short-term debt	381,000	1,909,000
Accounts payable	308,824	353,365
Customer deposits	55,033	59,327
Accrued general taxes	72,941	53,473
Accrued interest	41,484	30,964
Other current liabilities	404,703	396,126
Total current liabilities	1,313,728	3,112,049
Deferred income taxes and other credits:
Deferred income taxes and investment tax credits, net	774,465	768,868
Accumulated removal costs	500,052	480,583
Other deferred credits and other long-term liabilities	1,121,134	1,137,536
Total deferred income taxes and other credits	2,395,651	2,386,987
Total capitalization and liabilities	13,102,577	12,765,257
Southwest Gas Corporation
ASSETS
Gas plant	9,259,486	8,901,575
Less: accumulated depreciation	(2,641,407)	(2,538,508)
Construction work in progress	241,457	183,485
Net regulated operations plant	6,859,536	6,546,552
Other property and investments, net	145,561	153,093
Current assets:
Cash and cash equivalents	25,151	38,691
Accounts receivable, net of allowance	103,619	169,666
Accrued utility revenue	41,300	84,900
Income taxes receivable, net	2,619	7,826
Deferred purchased gas costs	381,351	291,145
Receivable from parent	95	1,031
Prepaid and other current assets	243,297	242,243
Total current assets	797,432	835,502
Noncurrent assets:
Goodwill	10,095	10,095
Deferred charges and other assets	381,145	405,021
Total noncurrent assets	391,240	415,116
Total assets	8,193,769	7,950,263
Capitalization:
Common stock	49,112	49,112
Additional paid-in capital	1,622,620	1,618,911
Accumulated other comprehensive loss, net	(43,121)	(46,913)
Retained earnings	900,428	906,827
Total equity	2,529,039	2,527,937
Long-term debt, less current maturities	3,042,082	2,440,603
Total capitalization	5,571,121	4,968,540
Current liabilities:
Current maturities of long-term debt	0	275,000
Short-term debt	225,000	250,000
Accounts payable	150,572	234,070
Customer deposits	51,833	56,127
Accrued general taxes	66,582	53,064
Accrued interest	30,685	22,926
Other current liabilities	139,217	146,422
Total current liabilities	663,889	1,037,609
Deferred income taxes and other credits:
Deferred income taxes and investment tax credits, net	666,604	638,828
Accumulated removal costs	442,000	424,000
Other deferred credits and other long-term liabilities	850,155	881,286
Total deferred income taxes and other credits	1,958,759	1,944,114
Total capitalization and liabilities	$ 8,193,769	$ 7,950,263

CONDENSED CONSOLIDATED STATEMENTS OF INCOME - Southwest - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Regulated operations revenues	$ 367,122	$ 255,848	$ 1,550,684	$ 1,070,576	$ 2,001,898	$ 1,445,066
Operating expenses:
Net cost of gas sold	100,991	63,710	547,769	296,227	682,449	374,449
Operations and maintenance	154,236	122,927	479,330	334,450	618,026	437,602
Depreciation and amortization	116,933	91,380	347,589	267,670	450,960	354,688
Taxes other than income taxes	23,356	20,109	70,778	60,134	90,987	76,087
Total operating expenses	1,075,651	865,396	3,275,026	2,340,005	4,245,925	3,101,290
Operating income (loss)	49,937	23,300	264,091	256,019	377,619	408,814
Other income and (expenses):
Net interest deductions	(64,373)	(31,298)	(165,942)	(81,201)	(203,939)	(109,537)
Other income (deductions)	1,593	(3,112)	2	(3,975)	478	282
Total other income and (expenses)	(62,780)	(34,410)	(165,940)	(85,176)	(203,461)	(109,255)
Income (loss) before income taxes	(12,843)	(11,110)	98,151	170,843	174,158	299,559
Income tax expense (benefit)	(1,525)	(1,816)	18,300	34,818	23,130	58,498
Net income (loss) attributable to Southwest Gas Holdings, Inc.	(12,309)	(11,576)	77,294	130,836	147,237	234,380
Southwest Gas Corporation
Regulated operations revenues	303,944	255,848	1,358,425	1,070,576	1,809,639	1,445,066
Operating expenses:
Net cost of gas sold	100,441	63,710	544,216	296,227	678,896	374,449
Operations and maintenance	121,537	119,708	368,984	328,980	478,554	431,795
Depreciation and amortization	64,390	61,359	192,434	187,688	258,144	249,118
Taxes other than income taxes	20,693	20,109	62,443	60,134	82,652	76,087
Total operating expenses	307,061	264,886	1,168,077	873,029	1,498,246	1,131,449
Operating income (loss)	(3,117)	(9,038)	190,348	197,547	311,393	313,617
Other income and (expenses):
Net interest deductions	(29,417)	(24,922)	(84,660)	(71,263)	(110,957)	(97,259)
Other income (deductions)	1,678	(4,287)	(440)	(4,902)	(97)	(545)
Total other income and (expenses)	(27,739)	(29,209)	(85,100)	(76,165)	(111,054)	(97,804)
Income (loss) before income taxes	(30,856)	(38,247)	105,248	121,382	200,339	215,813
Income tax expense (benefit)	(8,657)	(10,703)	17,918	18,798	28,458	33,679
Net income (loss) attributable to Southwest Gas Holdings, Inc.	$ (22,199)	$ (27,544)	$ 87,330	$ 102,584	$ 171,881	$ 182,134

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - Southwest - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Net income (loss)	$ (11,318)	$ (9,294)	$ 79,851	$ 136,025	$ 151,028	$ 241,061
Defined benefit pension plans:
Net actuarial gain (loss)	0	0	0	0	44,974	(43,730)
Amortization of prior service cost	34	183	100	547	282	766
Amortization of net actuarial loss	6,616	8,474	19,847	25,420	28,321	32,608
Regulatory adjustment	(5,524)	(7,277)	(16,571)	(21,831)	(61,767)	2,959
Net defined benefit pension plans	1,126	1,380	3,376	4,136	11,810	(7,397)
Forward-starting interest rate swaps (“FSIRS”):
Amounts reclassified into net income (loss)	0	413	416	1,240	828	1,653
Net forward-starting interest rate swaps	0	413	416	1,240	828	1,653
Total other comprehensive income (loss), net of tax	(4,704)	(263)	(3,471)	5,052	5,719	(3,168)
Comprehensive income (loss)	(16,022)	(9,557)	76,380	141,077	156,747	237,893
Southwest Gas Corporation
Net income (loss)	(22,199)	(27,544)	87,330	102,584	171,881	182,134
Defined benefit pension plans:
Net actuarial gain (loss)	0	0	0	0	44,974	(43,730)
Amortization of prior service cost	34	183	100	547	282	766
Amortization of net actuarial loss	6,616	8,474	19,847	25,420	28,321	32,608
Regulatory adjustment	(5,524)	(7,277)	(16,571)	(21,831)	(61,767)	2,959
Net defined benefit pension plans	1,126	1,380	3,376	4,136	11,810	(7,397)
Forward-starting interest rate swaps (“FSIRS”):
Amounts reclassified into net income (loss)	0	413	416	1,240	828	1,653
Net forward-starting interest rate swaps	0	413	416	1,240	828	1,653
Total other comprehensive income (loss), net of tax	1,126	1,793	3,792	5,376	12,638	(5,744)
Comprehensive income (loss)	$ (21,073)	$ (25,751)	$ 91,122	$ 107,960	$ 184,519	$ 176,390

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - Southwest - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
CASH FLOW FROM OPERATING ACTIVITIES:
Net income (loss)	$ 79,851	$ 136,025	$ 151,028	$ 241,061
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	347,589	267,670	450,960	354,688
Deferred income taxes	22,955	45,374	38,793	58,339
Changes in current assets and liabilities:
Accounts receivable, net of allowance	(78,719)	(62,081)	(68,192)	(68,714)
Accrued utility revenue	43,600	42,700	(1,600)	(3,200)
Deferred purchased gas costs	(92,200)	(293,410)	(142,518)	(317,070)
Accounts payable	(29,353)	(51,086)	72,159	251
Accrued taxes	18,352	5,954	5,673	3,134
Other current assets and liabilities	(1,039)	23,289	(113,537)	9,531
Gain on sale of property	(5,215)	(5,365)	(6,756)	(6,632)
Changes in undistributed stock compensation	7,855	7,676	9,473	9,001
Equity AFUDC	(912)	0	(912)	(1,311)
Changes in deferred charges and other assets	16,417	(7,956)	10,832	(21,373)
Changes in other liabilities and deferred credits	(25,826)	(57,269)	(42,186)	(67,922)
Net cash provided by operating activities	303,355	51,521	363,217	189,783
CASH FLOW FROM INVESTING ACTIVITIES:
Construction expenditures and property additions	(612,516)	(506,737)	(821,405)	(699,368)
Changes in customer advances	23,222	7,940	31,256	14,282
Other	4,005	14,755	7,506	17,238
Net cash used in investing activities	(604,098)	(1,314,437)	(2,325,317)	(1,497,993)
CASH FLOW FROM FINANCING ACTIVITIES:
Dividends paid	(118,980)	(102,292)	(154,910)	(134,479)
Issuance of long-term debt, net	770,240	1,654,960	775,976	1,666,718
Retirement of long-term debt	(422,356)	(406,815)	(468,205)	(473,926)
Change in credit facility and commercial paper	8,000	(150,000)	138,000	(58,000)
Withholding remittance - share-based compensation	(2,105)	(1,254)	(2,115)	(1,254)
Other	(19,929)	(4,355)	(16,303)	(6,161)
Net cash provided by financing activities	254,019	1,366,056	1,951,421	1,470,320
Change in cash and cash equivalents	(47,425)	103,338	(11,418)	162,745
Cash and cash equivalents at beginning of period	222,697	83,352	186,690	23,945
Cash and cash equivalents at end of period	175,272	186,690	175,272	186,690
SUPPLEMENTAL INFORMATION:
Interest paid, net of amounts capitalized	146,792	57,128	194,016	98,567
Income taxes paid (received), net	10,317	7,665	6,860	12,720
Southwest Gas Corporation
CASH FLOW FROM OPERATING ACTIVITIES:
Net income (loss)	87,330	102,584	171,881	182,134
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	192,434	187,688	258,144	249,118
Deferred income taxes	26,579	35,800	44,016	55,164
Changes in current assets and liabilities:
Accounts receivable, net of allowance	66,048	43,430	(188)	(22,766)
Accrued utility revenue	43,600	42,700	(1,600)	(3,200)
Deferred purchased gas costs	(90,206)	(293,410)	(140,524)	(317,070)
Accounts payable	(71,899)	(42,536)	28,401	17,396
Accrued taxes	18,725	5,396	21,082	(12,045)
Other current assets and liabilities	(5,908)	18,608	(94,787)	(7,739)
Gain on sale of property	(1,503)	0	(1,503)	0
Changes in undistributed stock compensation	4,993	5,437	5,948	6,239
Equity AFUDC	(248)	0	(248)	(1,311)
Changes in deferred charges and other assets	1,112	(18,726)	(8,905)	(35,329)
Changes in other liabilities and deferred credits	(26,467)	(55,905)	(42,948)	(68,509)
Net cash provided by operating activities	244,590	31,066	238,769	42,082
CASH FLOW FROM INVESTING ACTIVITIES:
Construction expenditures and property additions	(485,825)	(415,398)	(672,410)	(582,393)
Changes in customer advances	23,222	7,940	31,255	14,282
Other	(1,005)	65	(1,102)	653
Net cash used in investing activities	(463,608)	(407,393)	(642,257)	(567,458)
CASH FLOW FROM FINANCING ACTIVITIES:
Contributions from parent	0	202,583	0	248,544
Dividends paid	(92,200)	(82,000)	(121,600)	(109,000)
Issuance of long-term debt, net	593,862	297,318	593,862	297,318
Retirement of long-term debt	(275,000)	0	(275,000)	0
Change in credit facility and commercial paper	8,000	(150,000)	138,000	(58,000)
Change in short-term debt	(25,000)	193,000	(25,000)	250,000
Withholding remittance - share-based compensation	(2,011)	(1,254)	(2,020)	(1,254)
Other	(2,173)	(1,632)	(2,361)	(1,708)
Net cash provided by financing activities	205,478	458,015	305,881	625,900
Change in cash and cash equivalents	(13,540)	81,688	(97,607)	100,524
Cash and cash equivalents at beginning of period	38,691	41,070	122,758	22,234
Cash and cash equivalents at end of period	25,151	122,758	25,151	122,758
SUPPLEMENTAL INFORMATION:
Interest paid, net of amounts capitalized	76,141	53,220	113,161	92,778
Income taxes paid (received), net	$ 5	$ 0	$ (13,524)	$ 3,359

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY - Southwest - USD ($) $ in Thousands	Total	Southwest Gas Corporation	Common stock shares	Common stock shares Southwest Gas Corporation	Additional paid-in capital	Additional paid-in capital Southwest Gas Corporation	Accumulated other comprehensive loss	Accumulated other comprehensive loss Southwest Gas Corporation	Retained earnings	Retained earnings Southwest Gas Corporation
Beginning balance (in shares) at Dec. 31, 2020			57,193,000
Beginning balance at Dec. 31, 2020			$ 58,823		$ 1,609,155	$ 1,410,345	$ (61,003)	$ (61,135)	$ 1,067,978	$ 835,146
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)									130,836	102,584
Share-based compensation						4,868				(685)
Contributions from Southwest Gas Holdings, Inc.						202,583
Dividends declared to Southwest Gas Holdings, Inc.									(106,303)	(85,400)
Net actuarial gain arising during period, less amortization of unamortized benefit plan cost, net of tax							4,136	4,136
FSIRS amounts reclassified to net income, net of tax	$ 1,240	$ 1,240					1,240	1,240
Ending balance (in shares) at Sep. 30, 2021			60,379,000	47,482,000
Ending balance at Sep. 30, 2021		2,462,794	$ 62,009	$ 49,112	1,823,889	1,617,796	(55,951)	(55,759)	1,079,869	851,645
Beginning balance (in shares) at Jun. 30, 2021			59,088,000
Beginning balance at Jun. 30, 2021			$ 60,718		1,733,572	1,529,419	(55,688)	(57,552)	1,108,279	908,757
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)									(11,576)	(27,544)
Share-based compensation						1,435				(168)
Contributions from Southwest Gas Holdings, Inc.						86,942
Dividends declared to Southwest Gas Holdings, Inc.									(36,098)	(29,400)
Net actuarial gain arising during period, less amortization of unamortized benefit plan cost, net of tax							1,380	1,380
FSIRS amounts reclassified to net income, net of tax	413	413					413	413
Ending balance (in shares) at Sep. 30, 2021			60,379,000	47,482,000
Ending balance at Sep. 30, 2021		2,462,794	$ 62,009	$ 49,112	1,823,889	1,617,796	(55,951)	(55,759)	1,079,869	851,645
Increase (Decrease) in Stockholders' Equity [Roll Forward]
FSIRS amounts reclassified to net income, net of tax	$ 828	828
Ending balance (in shares) at Sep. 30, 2022	67,063,730		67,064,000	47,482,000
Ending balance at Sep. 30, 2022		2,529,039	$ 68,694	$ 49,112	2,283,250	1,622,620	(50,232)	(43,121)	1,111,203	900,428
Beginning balance (in shares) at Dec. 31, 2021	60,422,081		60,422,000
Beginning balance at Dec. 31, 2021			$ 62,052		1,824,216	1,618,911	(46,761)	(46,913)	1,114,313	906,827
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)									77,294	87,330
Share-based compensation						3,709				(729)
Contributions from Southwest Gas Holdings, Inc.						0
Dividends declared to Southwest Gas Holdings, Inc.									(125,337)	(93,000)
Net actuarial gain arising during period, less amortization of unamortized benefit plan cost, net of tax							3,376	3,376
FSIRS amounts reclassified to net income, net of tax	$ 416	416					416	416
Ending balance (in shares) at Sep. 30, 2022	67,063,730		67,064,000	47,482,000
Ending balance at Sep. 30, 2022		2,529,039	$ 68,694	$ 49,112	2,283,250	1,622,620	(50,232)	(43,121)	1,111,203	900,428
Beginning balance (in shares) at Jun. 30, 2022			67,004,000
Beginning balance at Jun. 30, 2022			$ 68,634		2,279,493	1,622,006	(45,528)	(44,247)	1,156,253	952,725
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)									(12,309)	(22,199)
Share-based compensation						614				(98)
Contributions from Southwest Gas Holdings, Inc.						0
Dividends declared to Southwest Gas Holdings, Inc.									(41,696)	(30,000)
Net actuarial gain arising during period, less amortization of unamortized benefit plan cost, net of tax							1,126	1,126
FSIRS amounts reclassified to net income, net of tax	$ 0	0					0	0
Ending balance (in shares) at Sep. 30, 2022	67,063,730		67,064,000	47,482,000
Ending balance at Sep. 30, 2022		$ 2,529,039	$ 68,694	$ 49,112	$ 2,283,250	$ 1,622,620	$ (50,232)	$ (43,121)	$ 1,111,203	$ 900,428

- Definition

Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

+ References

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+ Details

Background, Organization, and Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2022

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Background, Organization, and Summary of Significant Accounting Policies

Note 1 – Background, Organization, and Summary of Significant Accounting Policies

Nature of Operations. Southwest Gas Holdings, Inc. (together with its subsidiaries, the “Company”) is a holding company, owning all of the shares of common stock of Southwest Gas Corporation (“Southwest” or the “natural gas distribution” segment), all of the shares of common stock of Centuri Group, Inc. (“Centuri,” or the “utility infrastructure services” segment), and all of the shares of common stock of MountainWest Pipelines Holding Company (“MountainWest,” or the “pipeline and storage” segment).

Southwest is engaged in the business of purchasing, distributing, and transporting natural gas for customers in portions of Arizona, Nevada, and California. Public utility rates, practices, facilities, and service territories of Southwest are subject to regulatory oversight. The timing and amount of rate relief can materially impact results of operations. Natural gas purchases and the timing of related recoveries can materially impact liquidity. Results for the natural gas distribution segment are higher during winter periods due to the seasonality incorporated in its regulatory rate structures.

The Company completed the acquisition of Dominion Energy Questar Pipeline, LLC and related entities (“Questar Pipelines”) in December 2021 and formed MountainWest, which owns all of the membership interests in Questar Pipelines. In April 2022, the Company completed a general rebranding of the Questar Pipelines entities under the MountainWest name. The acquired operations further diversify the Company’s business in the midstream sector, with an expansion of interstate natural gas pipelines and underground storage services, primarily composed of regulated operations under the jurisdiction of the Federal Energy Regulatory Commission (the “FERC”), thereby expanding natural gas transportation services into Utah, Wyoming, and Colorado. See Note 8 - Business Acquisitions for more information.

Centuri is a strategic utility infrastructure services company dedicated to partnering with North America’s gas and electric providers to build and maintain the energy network that powers millions of homes across the United States (“U.S.”) and Canada. Centuri derives revenue primarily from installation, replacement, repair, and maintenance of energy networks. Centuri operates in the U.S., primarily as NPL, Neuco, Linetec, and Riggs Distler, and in Canada, primarily as NPL Canada. Utility infrastructure services activity is seasonal in many of Centuri’s operating areas. Peak periods are the summer and fall months in colder climate areas, such as the northeastern and midwestern U.S. and in Canada. In warmer climate areas, such as the southwestern and southeastern U.S., utility infrastructure services activity continues year round.

Centuri completed the acquisition of Drum Parent LLC (“Drum”), including Drum’s most significant operating subsidiary, Riggs Distler, in August 2021, thereby expanding Centuri’s electric infrastructure services footprint in the northeast and mid-Atlantic regions of the U.S. See Note 8 - Business Acquisitions for more information.

In March 2022, the Company announced that its Board of Directors (the “Board”) had determined to separate Centuri from the Company and authorized management to complete the separation within nine to twelve months. Initially it was contemplated that the Centuri separation would take the form of a spin-off. Then, in April 2022, as a result of interest in the Company well in excess of an earlier tender offer to other shareholders by an activist stockholder (affiliates of Carl C. Icahn), the Board authorized the review of a full range of strategic alternatives to maximize stockholder value. As part of this process, a strategic transactions committee of the Board (the “Strategic Transactions Committee”), consisting entirely of independent directors, began evaluating a sale of the Company, as well as a range of alternatives, including, but not limited to, a separate sale of its business units and/or pursuing the spin-off of Centuri (collectively, the “Strategic Review”). On August 3, 2022, the Company announced that the Board had unanimously determined that the best path forward to maximize value for all stockholders is to (i) focus on its strategic plan while concluding the strategic review process for Southwest Gas Holdings, Inc. and Southwest Gas Corporation; (ii) continue to review strategic alternatives for MountainWest; and (iii) continue to review strategic alternatives for Centuri, including a sale or spin-off of Centuri, among others.

On May 6, 2022, the Company entered into a Cooperation Agreement (the “Cooperation Agreement”) with Carl C. Icahn and the persons and entities referenced therein (collectively, the “Icahn Group”). In accordance with the Cooperation Agreement, among other things, John P. Hester, then President and Chief Executive Officer of the Company and Southwest, retired from his positions with the Company and Southwest and resigned from the Board. Karen S. Haller, the Company’s former Executive Vice President/Chief Legal and Administrative Officer, was appointed President and Chief Executive Officer of the Company and Chief Executive Officer of Southwest, and was appointed as a member of the Board effective immediately following the completion of the Company’s 2022 annual meeting of stockholders (the “2022 Annual Meeting”). Justin L. Brown, formerly Southwest’s Senior Vice President/General Counsel, was appointed as President of Southwest.

In addition, pursuant to the Cooperation Agreement, the Company agreed to appoint three new directors, Andrew W. Evans, H. Russell Frisby, Jr., and Henry P. Linginfelter (collectively, the “Initial Icahn Designees”), to the Board, which became effective immediately following the 2022 Annual Meeting. Also pursuant to the Cooperation Agreement, on May 27, 2022, the Icahn group informed the Company that it would cause Mr. Frisby to resign from the Board and requested that Andrew J. Teno be appointed to the Board to fill the vacancy created by Mr. Frisby’s resignation. As a result, on May 27, Mr. Frisby resigned from

the Board, effective immediately, and the Board appointed Mr. Teno to fill the vacancy created by Mr. Frisby’s resignation, effective immediately. The Icahn Group’s ability to designate directors to the Board is subject to certain ownership thresholds. Consistent with the terms of the Cooperation Agreement and pursuant to the terms of that certain Letter Agreement, dated as of August 3, 2022 (the “Letter Agreement” and together with the Cooperation Agreement, the “Initial Cooperation Agreement”), by and between the Company and the Icahn Group, the Company agreed to extend the date by which the Icahn Group was permitted to appoint a director other than Mr. Frisby to replace Mr. Cárdenas on the Board. On August 9, 2022, in accordance with the terms of the Initial Cooperation Agreement, Ruby Sharma was appointed to the Board to replace Mr. Cárdenas.

The Initial Cooperation Agreement required the Board to expand the Strategic Transactions Committee from three directors to six directors, comprised of the existing members of the Strategic Transactions Committee in addition to the three Initial Icahn Designees. Also, as the Icahn Group has the ability to designate at least three members of the Board, such individuals are to be included on the Strategic Transactions Committee. If the Icahn Group may only designate two members of the Board, then both would serve on the Strategic Transactions Committee.

On May 9, 2022, the Company also entered into Amendment No. 1 to the Rights Agreement dated October 10, 2021 (the “Original Rights Agreement” and as amended, the “Amended Rights Agreement”), to increase the triggering percentage from 10% to 24.9% pursuant to the terms of the Initial Cooperation Agreement and permit the subsequent consummation of the Offer. The Amended Rights Agreement expired on October 9, 2022. See details in the Company’s and Southwest’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (the “2021 Form 10-K”) regarding the Original Rights Agreement, as well as Note 4 – Common Stock in this current report on Form 10-Q.

An earlier civil suit (initiated in November 2021) by Icahn entities against the Company and certain directors and officers of the Company was subject to a stipulation of dismissal as part of the Initial Cooperation Agreement. The Initial Cooperation Agreement also provided for the reimbursement by the Company of certain out-of-pocket third-party expenses, including certain legal fees, incurred by the Icahn Group.

On October 24, 2022, the Company and the Icahn Group entered into an Amended and Restated Cooperation Agreement (the “Amended Cooperation Agreement”), which amended, restated, superseded, and replaced in its entirety the Initial Cooperation Agreement. Please see Note 9 - Subsequent Events for additional information about the Amended Cooperation Agreement.

Basis of Presentation. The condensed consolidated financial statements of Southwest Gas Holdings, Inc. and subsidiaries and Southwest (with its subsidiaries) included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). The year-end 2021 condensed balance sheet data was derived from audited financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) have been condensed or omitted pursuant to such rules and regulations. No substantive change has occurred with regard to the Company’s business segments on the whole during the recently completed quarter.

The preparation of the condensed consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. In the opinion of management, all adjustments, consisting of normal recurring items and estimates necessary for a fair depiction of results for the interim periods, have been made.

These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in the 2021 Annual Report to Stockholders, which is incorporated by reference into the 2021 Form 10-K.

Other Property and Investments. Other property and investments on Southwest’s and the Company’s Condensed Consolidated Balance Sheets includes:


(Thousands of dollars)	September 30, 2022		December 31, 2021
Net cash surrender value of COLI policies	$	141,705	$	149,947
Other property	3,856		3,146
Total Southwest Gas Corporation	145,561		153,093
Non-regulated property, equipment, and intangibles	1,704,354		1,616,392
Non-regulated accumulated provision for depreciation and amortization	(595,393)		(512,343)
Other property and investments	56,812		59,337
Total Southwest Gas Holdings, Inc.	$	1,311,334	$	1,316,479

Included in the table above are the net cash surrender values of company-owned life insurance (“COLI”) policies. These life insurance policies on members of management and other key employees are used by Southwest to indemnify itself against the loss of talent, expertise, and knowledge, as well as to provide indirect funding for certain nonqualified benefit plans. The term non-regulated in regard to assets and related balances in the table above is in reference to the non-rate regulated operations of Centuri, and to a more limited extent, certain assets of MountainWest.

Cash and Cash Equivalents. Cash and cash equivalents of the Company include $56 million and $20 million of money market fund investments at September 30, 2022 and December 31, 2021, respectively. The money market fund investments for Southwest were insignificant at both balance sheet dates. These investments fall within Level 2 of the fair value hierarchy, due to the asset valuation methods used by money market funds.

Noncash investing activities for the Company and Southwest include capital expenditures that were not yet paid, thereby remaining in accounts payable, the amounts related to which declined by approximately $4.8 million and $11.6 million during the nine months ended September 30, 2022, respectively, and increased $16.1 million and $9.4 million during the twelve months ended September 30, 2022, respectively.

Accounts Receivable, net of allowances. Following an earlier moratorium on account disconnections amidst the COVID-19 environment, account collection efforts resumed in 2021 in all jurisdictions in which Southwest operates. Ultimately, some accounts may not be collected, and if collection is unsuccessful, such accounts are written off. Estimates as to collectibility are made on an ongoing basis. However, Southwest continues to actively work with customers experiencing financial hardship by means of flexible payment options and partnering with assistance agencies. The cost of gas included in customer rates also influences account balances at each reporting date.

Deferred Purchased Gas Costs. The various regulatory commissions have established procedures to enable the rate-regulated companies to adjust billing rates for changes in the cost of natural gas purchased. The difference between the current cost of gas purchased and the cost of gas recovered in billed rates is deferred. Generally, these deferred amounts are recovered or refunded within one year.

Prepaid and other current assets. Prepaid and other current assets for Southwest include, among other things, materials and operating supplies of $76.5 million at September 30, 2022 and $62.9 million at December 31, 2021 (carried at weighted average cost). For the Company, there were materials and operating supplies of $80.8 million and $67.4 million at September 30, 2022 and December 31, 2021, respectively, which included amounts for MountainWest. Also included in the balance for both Southwest and the Company was $15.5 million and $51.6 million as of September 30, 2022 and December 31, 2021, respectively, in accrued purchased gas cost.

Goodwill. Goodwill is assessed as of October 1st each year for impairment, or more frequently, if circumstances indicate it may be more likely than not that the fair value of a reporting unit is less than its carrying value. The Company’s reporting units for goodwill are its operating segments, which are also its reportable segments. The acquisition of MountainWest resulted in a new reportable segment, which was assessed for impairment for the first time in 2022. Management considered whether the results of strategic initiatives in 2022 indicated it was more likely than not that the fair value of the Company’s reporting units were less than their carrying amounts. Through management’s assessments, no impairment was deemed to have occurred. However, there can be no assurances that future assessments of goodwill will not result in an impairment, and various factors, including changes in the business, strategic initiatives, economic conditions, governmental monetary policies, interest rates, or others, on their own or in combination with each other, could result in the fair value of reporting units being lower than their carrying values. Goodwill in the Natural Gas Distribution operations of Southwest, and across all operations of the Company, is included in their respective Condensed Consolidated Balance Sheets as follows:


(Thousands of dollars)	Natural Gas Distribution		Utility Infrastructure Services		Pipeline and Storage		Total Company
December 31, 2021	$	10,095	$	785,058	$	986,179	$	1,781,332
Measurement-period adjustments from Riggs Distler acquisition (a)	—		(1,924)		—		(1,924)
Measurement-period adjustments from MountainWest acquisition (a)	—		—		(28,177)		(28,177)
Foreign currency translation adjustment	—		(8,264)		—		(8,264)
September 30, 2022	$	10,095	$	774,870	$	958,002	$	1,742,967

(a) See Note 8 - Business Acquisitions for details regarding measurement-period adjustments.

Other Current Liabilities. Management recognizes in its balance sheets various liabilities that are expected to be settled through future cash payment within the next twelve months, including amounts payable under regulatory mechanisms, customary accrued expenses for employee compensation and benefits, declared but unpaid dividends, and miscellaneous other accrued liabilities. Other current liabilities for the Company include $41.6 million and $36 million of dividends declared as of September 30, 2022 and December 31, 2021, respectively.

Other Income (Deductions). The following table provides the composition of significant items included in Other income (deductions) in Southwest’s and the Company’s Condensed Consolidated Statements of Income:


	Three Months Ended September 30,				Nine Months Ended September 30,				Twelve Months Ended September 30,
(Thousands of dollars)	2022		2021		2022		2021		2022		2021
Southwest Gas Corporation:
Change in COLI policies	$	(1,500)	$	—	$	(8,700)	$	5,800	$	(5,700)	$	14,000
Interest income	4,356		1,365		10,355		3,312		12,156		4,113
Equity AFUDC	91		—		248		—		248		1,311
Other components of net periodic benefit cost	(188)		(3,506)		(563)		(10,516)		(4,068)		(15,522)
Miscellaneous income and (expense)	(1,081)		(2,146)		(1,780)		(3,498)		(2,733)		(4,447)
Southwest Gas Corporation - total other income (deductions)	1,678		(4,287)		(440)		(4,902)		(97)		(545)
Centuri, MountainWest, and Southwest Gas Holdings, Inc.:

Foreign transaction gain (loss)	(182)		(7)		35		(19)		32		(19)
Equity AFUDC	246		—		664		—		664		—
Equity in earnings of unconsolidated investments	624		67		1,867		168		1,925		159
Miscellaneous income and (expense)	(773)		1,115		(2,124)		778		(2,046)		687
Southwest Gas Holdings, Inc. - total other income (deductions)	$	1,593	$	(3,112)	$	2	$	(3,975)	$	478	$	282

Included in the table above is the change in cash surrender values of COLI policies (including net death benefits recognized). Current tax regulations provide for tax-free treatment of life insurance (death benefit) proceeds. Therefore, changes in the cash surrender values of COLI policies, as they progress towards the ultimate death benefits, are also recorded without tax consequences. Interest income primarily relates to Southwest’s regulatory asset balances, including its deferred purchased gas cost mechanisms. Refer also to the discussion of Other Property and Investments above and to Note 2 – Components of Net Periodic Benefit Cost.

Redeemable Noncontrolling Interests. In connection with the acquisition of Linetec in November 2018, the previous owner retained a 20% equity interest in that entity, the reduction of which is subject to certain rights based on the passage of time or upon the occurrence of certain triggering events. Effective January 2022, the Company, through Centuri, had the right, but not the obligation, to purchase at fair value (subject to a floor) a portion of the interest held by the previous owner, and in incremental amounts each year thereafter. In March 2022, the parties agreed to a partial redemption based on these provisions, and as a result, Centuri paid $39.6 million to the previous owner of Linetec for a 5% equity interest in Linetec, thereby reducing the balance continuing to be redeemable to 15% under the terms of the original agreement. In order to fund the redemption, Southwest Gas Holdings, Inc. contributed capital to Centuri.

Certain members of Riggs Distler management have a 1.42% interest in Drum, which is redeemable, subject to certain rights based on the passage of time or upon the occurrence of certain triggering events.

Significant changes in the value of the redeemable noncontrolling interests, above a floor determined at the establishment date, are recognized as they occur, and the carrying value is adjusted as necessary at each reporting date. The fair value is estimated using a market approach that utilizes certain financial metrics from guideline public companies of similar industry and operating characteristics. Based on the fair value model employed, the estimated redemption value of the Linetec redeemable noncontrolling interest decreased by approximately $45 million during the nine months ended September 30, 2022. Adjustment to the redemption value also impacts retained earnings, as reflected in the Company’s Condensed Consolidated Statement of Equity, but does not impact net income. The following depicts changes to the balances of the redeemable noncontrolling interests:


(Thousands of dollars):	Linetec		Drum		Total
Balance, December 31, 2021	$	184,148	$	12,569	$	196,717
Net income (loss) attributable to redeemable noncontrolling interests	2,582		(25)		2,557
Redemption value adjustments	(44,933)		—		(44,933)
Redemption of equity interest from noncontrolling party	(39,649)		—		(39,649)
Balance, September 30, 2022	$	102,148	$	12,544	$	114,692

Earnings Per Share. Basic earnings per share (“EPS”) in each period of this report were calculated by dividing net income attributable to Southwest Gas Holdings, Inc. by the weighted-average number of shares during those periods. Diluted EPS includes additional weighted-average common stock equivalents (performance shares and restricted stock units). Unless otherwise noted, the term “Earnings Per Share” refers to Basic EPS. A reconciliation of the denominator used in Basic and Diluted EPS calculations is shown in the following table:


	Three Months Ended September 30,		Nine Months Ended September 30,		Twelve Months Ended September 30,
(In thousands)	2022	2021	2022	2021	2022	2021
Weighted average basic shares	67,157	59,688	65,004	58,639	63,905	58,209
Effect of dilutive securities:
Restricted stock units (1)	168	128	144	103	146	103
Weighted average diluted shares	67,325	59,816	65,148	58,742	64,051	58,312

(1) The number of securities included 156,000 and 115,000 performance shares during the three months ending September 30, 2022 and 2021, 135,000 and 95,000 performance shares during the nine months ending September 30, 2022 and 2021, and 135,000 and 93,000 performance shares during the twelve months ending September 30, 2022 and 2021, respectively, the total of which was derived by assuming that target performance will be achieved during the relevant performance period.

Contingencies. Southwest maintains liability insurance for various risks associated with the operation of its natural gas pipelines and facilities. In connection with these liability insurance policies, Southwest is responsible for an initial deductible or self-insured retention amount per incident, after which the insurance carriers would be responsible for amounts up to the policy limits. For the policy year August 2022 to July 2023, these liability insurance policies require Southwest to be responsible for the first $1 million (self-insured retention) of each incident plus the first $4 million in aggregate claims above its self-insured retention in the policy year. In August 2021, a natural gas pipe operated by Southwest was involved in an explosion that injured four individuals and damaged property. The explosion was caused by a leak in the pipe, and is under investigation. Individuals that were injured have each brought legal claims against Southwest and other parties. If Southwest is deemed fully or partially responsible, Southwest estimates its net exposure could be equal to the self-insured retention of $5 million (the maximum noted above). In 2021, pursuant to Accounting Standards Codification 450, Contingencies, Southwest recorded a $5 million liability related to this incident reflecting the maximum noted above; an estimate of actual loss greater than this exposure (to be covered by insurance) cannot be estimated as of the date these financial statements are issued.

Other contingencies are also recognized where appropriate, if claims are brought, or expected to be brought, against the Company or Southwest, where management expects it may settle (or be required to settle) claims in cash, or in some cases, by means of insurance indemnification. For instance, the balance of such reserves was updated in the second quarter of 2022 for $6.2 million related to a contract dispute. The amount was paid in the third quarter of 2022 and the matter is now closed.

As described above, the November 2021 civil suit filed by the Icahn Group against the Company and certain officers and directors was subject to a stipulation of dismissal with prejudice in May 2022, pursuant to the terms of the Initial Cooperation Agreement.

On November 18, 2021, the City Pension Fund for Firefighters and Police Officers in the City of Miami Beach (“City Pension Fund”) commenced a putative class action lawsuit in the Court of Chancery for the State of Delaware on behalf of a putative class of persons who purchased the Company’s stock. The complaint was later amended on November 30, 2021. The amended complaint named the Company and the individual members of the Board as defendants. The complaint sought to assert breach of fiduciary duty claims, alleging that the Board’s recommendation that stockholders reject Icahn’s Offer to purchase shares of the Company’s common stock omitted material information about the Company’s financial analysis; and sought to have the Board approve Icahn’s slate of nominees as “continuing directors” under certain of the Company’s debt instruments. In March 2022, the City Pension Fund filed a motion for summary judgment on its claim; however, in April 2022, the City Pension Fund filed a notice of withdrawal of its motion for summary judgment. The Company believes that the claims lack merit and intends to vigorously defend against them.

Recent Accounting Standards Updates.

Accounting pronouncements effective or adopted in 2022:

In March 2020, the Financial Accounting Standards Board (the “FASB”) issued ASU 2020-04 “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting.” The update provides optional guidance for a limited time to ease the potential burden in accounting for, or recognizing the effects of, reference rate reform on financial reporting, including when modifying a contract (during the eligibility period covered by the update to Topic 848) to replace a reference rate affected by such reform. The update applies only to contracts and hedging relationships that reference the London Interbank Offered Rate (“LIBOR”) or another rate expected to be discontinued due to reference rate reform. The guidance was eligible to be applied upon issuance on March 12, 2020, and can generally be applied through December 31, 2022, and while a proposal by the FASB has occurred to extend the optional guidance to the full tenor of LIBOR expiration dates occurring after 2022, to date, no such update has been made effective. Management will monitor the impacts this update might have on the Company’s and Southwest’s consolidated financial statements and disclosures, and will reflect such appropriately, in the event that the optional guidance is elected. Management will also monitor further FASB action, if any, in regard to the full tenor of LIBOR expiration dates. See also LIBOR discussion in Note 5 – Debt.

In August 2020, the FASB issued ASU 2020-06 “Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging— Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity.” The update, amongst other amendments, improves the guidance related to the disclosures and earnings-per-share for convertible instruments and contracts in an entity’s own equity. The Company and Southwest adopted the update in the first quarter of 2022, the impact of which was not material to the consolidated financial statements of the Company or Southwest.

Components of Net Periodic Benefit Cost

9 Months Ended

Sep. 30, 2022

Retirement Benefits [Abstract]

Components of Net Periodic Benefit Cost

Note 2 – Components of Net Periodic Benefit Cost

Southwest has a noncontributory qualified retirement plan with defined benefits covering substantially all employees and a separate unfunded supplemental retirement plan (“SERP”), which is limited to officers. Southwest also provides postretirement benefits other than pensions (“PBOP”) to its qualified retirees for health care, dental, and life insurance. The defined benefit qualified retirement plan, SERP, and PBOP are not available to Southwest employees hired on or after January 1, 2022. Employees hired in 2022 or later periods are eligible for enhanced defined contributions as part of the Southwest 401(k) plan, rather than participating in the defined benefit retirement plan.

The service cost component of net periodic benefit costs included in the table below is a component of an overhead loading process associated with the cost of labor. The overhead process ultimately results in allocation of service cost to the same accounts to which productive labor is charged. As a result, service costs become components of various accounts, primarily operations and maintenance expense, net regulated operations plant, and deferred charges and other assets for both the Company and Southwest. The other components of net periodic benefit cost are reflected in Other income (deductions) on the Condensed Consolidated Statements of Income of each entity.


	Qualified Retirement Plan
	September 30,
	Three Months				Nine Months				Twelve Months
	2022		2021		2022		2021		2022		2021
(Thousands of dollars)
Service cost	$	11,028	$	10,289	$	33,084	$	30,869	$	43,374	$	39,443
Interest cost	11,251		10,108		33,753		30,324		43,861		41,714
Expected return on plan assets	(19,978)		(18,088)		(59,934)		(54,264)		(78,022)		(70,588)
Amortization of net actuarial loss	8,117		10,489		24,351		31,467		34,839		40,473
Net periodic benefit cost	$	10,418	$	12,798	$	31,254	$	38,396	$	44,052	$	51,042

	SERP
	September 30,
	Three Months				Nine Months				Twelve Months
	2022		2021		2022		2021		2022		2021
(Thousands of dollars)
Service cost	$	106	$	131	$	318	$	394	$	450	$	491
Interest cost	360		358		1,080		1,074		1,437		1,474
Amortization of net actuarial loss	588		661		1,763		1,981		2,424		2,433
Net periodic benefit cost	$	1,054	$	1,150	$	3,161	$	3,449	$	4,311	$	4,398

	PBOP
	September 30,
	Three Months				Nine Months				Twelve Months
	2022		2021		2022		2021		2022		2021
(Thousands of dollars)
Service cost	$	485	$	423	$	1,455	$	1,269	$	1,877	$	1,664
Interest cost	613		549		1,839		1,645		2,387		2,291
Expected return on plan assets	(807)		(810)		(2,421)		(2,430)		(3,230)		(3,282)
Amortization of prior service costs	44		239		132		719		372		1,007

Net periodic benefit cost	$	335	$	401	$	1,005	$	1,203	$	1,406	$	1,680

Revenue

9 Months Ended

Sep. 30, 2022

Revenue from Contract with Customer [Abstract]

Revenue

Note 3 – Revenue

The following information about the Company’s revenues is presented by segment. Southwest encompasses the natural gas distribution segment, Centuri encompasses the utility infrastructure services segment, and MountainWest encompasses the pipeline and storage segment. Certain disclosures, where materially consistent with those provided most recently in the 2021 Form 10-K, are not repeated below.

Natural Gas Distribution Segment:

Southwest’s operating revenues included on the Condensed Consolidated Statements of Income of both the Company and Southwest include revenue from contracts with customers, which is shown below, disaggregated by customer type, in addition to other categories of revenue:


	Three Months Ended September 30,				Nine Months Ended September 30,				Twelve Months Ended September 30,
(Thousands of dollars)	2022		2021		2022		2021		2022		2021
Residential	$	170,196	$	147,326	$	913,355	$	743,791	$	1,205,176	$	1,011,450
Small commercial	61,780		48,283		264,494		185,774		348,934		248,193
Large commercial	19,590		14,199		60,740		40,030		78,081		52,075
Industrial/other	13,319		9,608		34,064		30,352		46,025		37,505
Transportation	22,936		21,884		74,034		68,217		98,057		91,151
Revenue from contracts with customers	287,821		241,300		1,346,687		1,068,164		1,776,273		1,440,374
Alternative revenue program revenues (deferrals)	13,609		12,569		1,132		(5,335)		19,648		(2,740)
Other revenues (1)	2,514		1,979		10,606		7,747		13,718		7,432
Total Regulated operations revenues	$	303,944	$	255,848	$	1,358,425	$	1,070,576	$	1,809,639	$	1,445,066

(1) Amounts include late fees and other miscellaneous revenues, and may also include the impact of certain regulatory mechanisms, such as cost-of-service components in customer rates expected to be returned to customers in future periods. Also includes the impacts of a temporary moratorium on late fees and disconnection for nonpayment during the COVID-19 pandemic.

Utility Infrastructure Services Segment:

The following tables display Centuri’s revenue, reflected as Utility infrastructure services revenues on the Condensed Consolidated Statements of Income of the Company, representing revenue from contracts with customers disaggregated by service and contract types:


	Three Months Ended September 30,				Nine Months Ended September 30,				Twelve Months Ended September 30,
(Thousands of dollars)	2022		2021		2022		2021		2022		2021
Service Types:
Gas infrastructure services	$	467,751	$	393,122	$	1,147,302	$	961,836	$	1,487,806	$	1,287,552
Electric power infrastructure services	189,209		155,456		550,926		347,061		729,067		475,895
Other	101,506		84,270		290,205		216,551		404,773		301,591
Total Utility infrastructure services revenues	$	758,466	$	632,848	$	1,988,433	$	1,525,448	$	2,621,646	$	2,065,038


	Three Months Ended September 30,				Nine Months Ended September 30,				Twelve Months Ended September 30,
(Thousands of dollars)	2022		2021		2022		2021		2022		2021
Contract Types:
Master services agreement	$	637,582	$	467,869	$	1,700,416	$	1,160,199	$	2,193,195	$	1,573,247
Bid contract	120,884		164,979		288,017		365,249		428,451		491,791
Total Utility infrastructure services revenues	$	758,466	$	632,848	$	1,988,433	$	1,525,448	$	2,621,646	$	2,065,038

Unit price contracts	$	453,718	$	406,404	$	1,178,168	$	1,002,779	$	1,544,471	$	1,373,746
Fixed price contracts	117,983		64,632		333,313		149,681		451,374		197,447
Time and materials contracts	186,765		161,812		476,952		372,988		625,801		493,845
Total Utility infrastructure services revenues	$	758,466	$	632,848	$	1,988,433	$	1,525,448	$	2,621,646	$	2,065,038

The following table provides information about contracts receivable and revenue earned on contracts in progress in excess of billings (contract assets), both of which are included within Accounts receivable, net of allowances, as well as amounts billed in excess of revenue earned on contracts (contract liabilities), which are included in Other current liabilities as of September 30, 2022 and December 31, 2021 on the Company’s Condensed Consolidated Balance Sheets:


(Thousands of dollars)	September 30, 2022		December 31, 2021
Contracts receivable, net	$	398,345	$	296,005
Revenue earned on contracts in progress in excess of billings	253,966		214,774
Amounts billed in excess of revenue earned on contracts	31,877		11,860

The revenue earned on contracts in progress in excess of billings (contract asset) primarily relates to Centuri’s right to consideration for work completed but not billed and/or approved for billing at the reporting date. These contract assets are transferred to contracts receivable when the rights become unconditional. The amounts billed in excess of revenue earned (contract liability) primarily relate to the advance consideration received from customers for which work has not yet been completed. The change in this contract liability balance from December 31, 2021 to September 30, 2022 is due to increases in cash received, net of revenue recognized, from contracts that commenced during the period, offset by revenue recognized of approximately $11.9 million that was included in this balance as of January 1, 2022, after which time it became earned and the balance was reduced.

For contracts that have an original duration of one year or less, Centuri uses the practical expedient applicable to such contracts and does not consider/compute an interest component based on the time value of money. Furthermore, because of the short duration of these contracts, Centuri has not disclosed the transaction price for the remaining performance obligations as of the end of each reporting period or when the Company expects to recognize the revenue.

As of September 30, 2022, Centuri had 61 fixed price contracts with an original duration of more than one year. The aggregate amount of the transaction price allocated to the unsatisfied performance obligations of these contracts as of September 30, 2022 was $430.3 million. Centuri expects to recognize the remaining performance obligations over approximately the next 2.7 years; however, the timing of that recognition is largely within the control of the customer, including when the necessary materials required to complete the work are provided by the customer.

Utility infrastructure services contracts receivable consists of the following:


(Thousands of dollars)	September 30, 2022		December 31, 2021
Billed on completed contracts and contracts in progress	$	400,831	$	292,770
Other receivables	1,885		3,492
Contracts receivable, gross	402,716		296,262
Allowance for doubtful accounts	(4,371)		(257)
Contracts receivable, net	$	398,345	$	296,005

Pipeline and Storage Segment:

MountainWest derives revenue on the basis of services rendered, commodities delivered, or contracts settled and includes amounts yet to be billed to customers. MountainWest generates revenue and earnings from annual reservation payments under firm peaking storage and firm transportation contracts. Straight-fixed-variable rate designs are used to allow for recovery of substantially all fixed costs in demand or reservation charges, thereby reducing the earnings impact of volume changes on gas transportation and storage operations.

MountainWest receives upfront payment for certain storage services it provides to customers, which are considered to be contract liabilities. These payments are amortized to revenue over the term of the contract.

The primary types of sales and service activities reported as revenue from contracts with customers are FERC-regulated gas transportation and storage services, and to a lesser extent, natural gas liquid (“NGL”) revenues consisting primarily of NGL processing services, and other revenue (including natural gas sales, and services related to gathering and processing activities, as well as miscellaneous service revenue).

Transportation and storage contracts are primarily stand-ready service contracts that include fixed reservation and variable usage fees. Fixed fees are recognized ratably over the life of the contract as the stand-ready performance obligations are satisfied, while variable usage fees are recognized when MountainWest has a right to consideration from a customer in an amount that corresponds directly with the value to the customer of the performance obligation completed to date. Substantially all of MountainWest’s revenues are derived from performance obligations satisfied over time, rather than recognized at a single point in time. Payment for most sales and services varies by contract type, but is typically due within a month of billing.

MountainWest typically receives or retains NGLs and natural gas from customers when providing natural gas processing, transportation, or storage services. MountainWest records the fair value of NGLs received as service revenue recognized over time and recognizes revenue from the subsequent sale of the NGLs to customers upon delivery. MountainWest typically retains some natural gas under certain transportation service arrangements, intended to facilitate performance of the service and allow for natural losses that occur. As the intent of the retention amount is to enable fulfillment of the contract rather than to provide compensation for services, the fuel allowance is not included in revenue.

MountainWest Regulated operations revenues on the Condensed Consolidated Statements of Income of the Company include revenue from contracts with customers, which is shown below, disaggregated by categories of sales and service activities.


	Three Months Ended September 30,		Nine Months Ended September 30,
(Thousands of dollars)	2022
Regulated gas transportation and storage revenues	$	59,283	$	179,046
NGL revenues	1,469		4,838
Other revenues	2,385		8,244
Revenue from contracts with customers	63,137		192,128
Other revenues	41		131
Total Regulated operations revenues	$	63,178	$	192,259

MountainWest has certain multi-year contracts with fixed-price performance obligations that were unsatisfied (or partially unsatisfied) at the end of the reporting period, whereby revenue will be earned over time as MountainWest stands ready to provide service. These amounts are not material to the Company’s financial statements overall. MountainWest also has certain contract liabilities related to consideration received from customers with an obligation to transfer goods or services subsequent to the balance sheet date, amounts for which are generally consistent between December 31, 2021 and September 30, 2022 and are not material.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI https://asc.fasb.org/topic&trid=49130388

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+ Details

Common Stock

9 Months Ended

Sep. 30, 2022

Equity [Abstract]

Common Stock

Note 4 – Common Stock

Shares of the Company’s common stock are publicly traded on the New York Stock Exchange, under the ticker symbol “SWX.” Share-based compensation related to Southwest and Centuri is based on stock awards to be issued in shares of Southwest Gas Holdings, Inc.

On April 8, 2021, the Company entered into a Sales Agency Agreement between the Company and BNY Mellon Capital Markets, LLC and J.P. Morgan Securities LLC (the “Equity Shelf Program”) for the offer and sale of up to $500 million of common stock from time to time in an at-the-market offering program. The shares are issued pursuant to the Company’s automatic shelf registration statement on Form S-3 (File No. 333-251074), or “the Universal Shelf.” There was no activity under the Equity Shelf Program during the quarter ended September 30, 2022. The following table provides the life-to-date activity under that program through September 30, 2022:




Gross proceeds	$	158,180,343
Less: agent commissions	(1,581,803)
Net proceeds	$	156,598,540
Number of shares sold	2,302,407
Weighted average price per share	$	68.70

As of September 30, 2022, the Company had approximately $341.8 million in common stock available for sale under the program.

In March 2022, the Company issued, through a separate prospectus supplement under the Universal Shelf, an aggregate of 6.325 million shares of common stock, in an underwritten public offering price of $74.00 per share, resulting in proceeds to the Company of $452.3 million, net of an underwriters’ discount of $15.8 million. The Company used the net proceeds to repay a portion of the outstanding borrowings under the 364-day term loan credit agreement that was used to initially fund the MountainWest acquisition.

During the nine months ended September 30, 2022, the Company issued approximately 216,000 shares of common stock through the Restricted Stock/Unit Plan and Omnibus Incentive Plan.

Additionally, during the nine months ended September 30, 2022, the Company issued 100,000 shares of common stock through the Dividend Reinvestment and Stock Purchase Plan, raising approximately $7.8 million.

In connection with the entry into the Initial Cooperation Agreement (see Note 1 – Background, Organization, and Summary of Significant Accounting Policies), the Company entered into the Amended Rights Agreement to increase the beneficial ownership percentage included in the definition of “Acquiring Person” from 10% to 24.9% and to delete the concept of a “Passive Institutional Investor” to permit the Icahn Group to consummate the Offer. The Amended Rights Agreement expired on October 9, 2022.

Debt

9 Months Ended

Sep. 30, 2022

Debt Disclosure [Abstract]

Debt

Note 5 – Debt

Long-Term Debt

Long-term debt is recognized in the Company’s and Southwest’s Condensed Consolidated Balance Sheets generally at the carrying value of the obligations outstanding. Details surrounding the fair value and individual carrying values of instruments are provided in the table that follows.


	September 30, 2022				December 31, 2021
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
(Thousands of dollars)
Southwest Gas Corporation:
Debentures:
Notes, 6.1%, due 2041	$	125,000	$	113,398	$	125,000	$	166,380
Notes, 4.05%, due 2032	600,000		506,346		—		—
Notes, 3.875%, due 2022	—		—		250,000		250,603
Notes, 4.875%, due 2043	250,000		202,383		250,000		307,538
Notes, 3.8%, due 2046	300,000		203,559		300,000		329,055
Notes, 3.7%, due 2028	300,000		267,903		300,000		325,191
Notes, 4.15%, due 2049	300,000		213,972		300,000		342,030
Notes, 2.2%, due 2030	450,000		340,763		450,000		440,838
Notes, 3.18%, due 2051	300,000		182,976		300,000		292,116
8% Series, due 2026	75,000		80,108		75,000		92,623
Medium-term notes, 7.78% series, due 2022	—		—		25,000		25,122
Medium-term notes, 7.92% series, due 2027	25,000		26,413		25,000		31,555
Medium-term notes, 6.76% series, due 2027	7,500		7,494		7,500		8,949
Unamortized discount and debt issuance costs	(26,701)				(19,959)
	2,705,799				2,387,541
Revolving credit facility and commercial paper	138,000		138,000		130,000		130,000
Industrial development revenue bonds:
Tax-exempt Series A, due 2028	50,000		50,000		50,000		50,000
2003 Series A, due 2038	50,000		50,000		50,000		50,000
2008 Series A, due 2038	50,000		50,000		50,000		50,000
2009 Series A, due 2039	50,000		50,000		50,000		50,000
Unamortized discount and debt issuance costs	(1,717)				(1,938)
	198,283				198,062
Less: current maturities	—				(275,000)
Southwest Gas Corporation total long-term debt, less current maturities	$	3,042,082			$	2,440,603
Southwest Gas Holdings, Inc.:
SWH term loan facility	$	1,147,747	1,148,057		$	—	$	—
Centuri secured term loan facility	1,008,550		977,033		1,117,138		1,117,841
Centuri secured revolving credit facility	150,571		150,740		103,329		103,749
MountainWest unsecured senior notes, 3.53%, due in 2028	101,843		86,345		102,078		102,078
MountainWest unsecured senior notes, 4.875%, due in 2041	199,431		152,581		199,926		199,926
MountainWest unsecured senior notes, 3.91%, due in 2038	147,812		103,398		147,735		147,735
Other debt obligations	134,274		122,980		51,665		50,003
Unamortized discount and debt issuance costs	(25,234)				(24,466)
Less: current maturities	(41,485)				(22,324)
Southwest Gas Holdings, Inc. total long-term debt, less current maturities	$	5,865,591			$	4,115,684

Southwest has a $400 million credit facility that is scheduled to expire in April 2025. Southwest designates $150 million of associated capacity as long-term debt and the remaining $250 million for working capital purposes. Interest rates for the credit facility are calculated at either the Secured Overnight Financing Rate (“SOFR”) or an “alternate base rate,” plus in each case an applicable margin that is determined based on Southwest’s senior unsecured debt rating. At September 30, 2022, the applicable margin is 1.125% for loans bearing interest with reference to SOFR and 0.125% for loans bearing interest with reference to the alternative base rate. At September 30, 2022, $138 million was outstanding on the long-term portion of the facility (no borrowings were outstanding under the commercial paper program, discussed below). No borrowings were outstanding on the short-term portion of the facility.

Southwest has a $50 million commercial paper program. Issuances under the commercial paper program are supported by Southwest’s revolving credit facility and, therefore, do not represent additional borrowing capacity under the credit facility. Borrowings under the commercial paper program, if any, are designated as long-term debt. Interest rates for the program are calculated at the then current commercial paper rate. At September 30, 2022, as noted above, no borrowings were outstanding under the commercial paper program.

In March 2022, Southwest issued $600 million aggregate principal amount of 4.05% Senior Notes at a discount of 0.65%. The notes will mature in March 2032. Southwest used the net proceeds to redeem the $250 million 3.875% notes due in April 2022 and to repay outstanding amounts under its credit facility, with the remaining net proceeds used for general corporate purposes.

On September 26, 2022 (the “Amendment Date”), Southwest Gas Holdings, Inc., entered into Amendment No. 1 (“Amended Credit Agreement”) to the 364-day Term Loan Credit Agreement (the “Credit Agreement”). The Credit Agreement initially provided for a $1.6 billion delayed-draw term loan (the “Term Loan Facility”) to primarily fund the acquisition of the equity interests in MountainWest. As of the Amendment Date, approximately $1.15 billion in aggregate principal was outstanding under the Term Loan Facility, the same as that which was outstanding as of September 30, 2022. The Amended Credit Agreement, among other things, (1) extends the maturity date of the Term Loan to December 30, 2023, making the outstanding borrowings long-term as of September 30, 2022, and (2) replaces London Interbank Offered Rate (“LIBOR”) interest rate benchmarks with SOFR interest rate benchmarks. As part of the Amended Credit Agreement, the Company paid a non-refundable upfront fee in an amount equal to 0.10% of the aggregate principal amount outstanding as of the Amendment Date, and will pay additional fees based on any principal balance outstanding as of March 31, 2023, June 30, 2023, and September 30, 2023 of 0.10%, 0.15%, and 0.20%, respectively.

Centuri has a $1.545 billion secured revolving credit and term loan multi-currency facility. Amounts can be borrowed in either Canadian or U.S. dollars. The revolving credit facility matures on August 27, 2026 and the term loan facility matures on August 27, 2028. Interest rates for the revolving credit facility and term loan facility are based on either a “base rate,” LIBOR or CDOR, plus an applicable margin in either case. The capacity of the line of credit portion of the facility is $400 million; related amounts borrowed and repaid are available to be re-borrowed. The term loan portion of the facility has a limit of $1.145 billion. The obligations under the credit agreement are secured by present and future ownership interests in substantially all direct and indirect subsidiaries of Centuri, substantially all of the tangible and intangible personal property of each borrower, certain of their direct and indirect subsidiaries, and all products, profits, and proceeds of the foregoing. Centuri’s assets securing the facility at September 30, 2022 totaled $2.6 billion. At September 30, 2022, $1.159 billion in borrowings were outstanding under Centuri’s combined secured revolving credit and term loan facility. On November 4, 2022, Centuri amended the financial covenants of the revolving credit facility to increase the maximum total net leverage ratio during the period from December 31, 2022 through December 31, 2023. See Note 9 - Subsequent Events for additional information about the amended credit facility.

MountainWest has two private placement unsecured senior notes and a public unsecured senior note, with a combined carrying value of $449.1 million and aggregate principal amount of $430 million. The carrying value is higher than the principal balance as amounts outstanding were recorded at their fair values as of the December 31, 2021 acquisition date of the MountainWest entities.

Short-Term Debt

Southwest Gas Holdings, Inc. has a $200 million credit facility that is scheduled to expire in December 2026 and is primarily used for short-term financing needs. Interest rates for the credit facility are calculated at either SOFR or the “alternate base rate” plus in each case an applicable margin. There was $156 million outstanding under this credit facility as of September 30, 2022.

As indicated above, under Southwest’s $400 million credit facility, no short-term borrowings were outstanding at September 30, 2022.

In March 2022, Southwest amended its $250 million Term Loan (the “March 2021 Term Loan”), extending the maturity date to March 21, 2023 and replacing LIBOR interest rate benchmarks with SOFR interest rate benchmarks. The proceeds were

originally used to fund the increased cost of natural gas supply during the month of February 2021, caused by extreme weather conditions in the central U.S. There was $225 million outstanding under the March 2021 Term Loan as of September 30, 2022.

As disclosed in Note 1 – Background, Organization, and Summary of Significant Accounting Policies, the Company is exploring strategic alternatives, including a potential sale of MountainWest and/or Centuri. If MountainWest and/or Centuri is sold as part of the Strategic Review process, the proceeds will be used to repay the amounts borrowed to fund the acquisition. Otherwise, management intends to either issue long-term debt or equity securities to refinance the Term Loan Facility.

Management believes that its refinancing plan is probable based on the Company’s ability to generate consistent cash flows, its current credit ratings, its relationships with its lenders and its prior history of successfully raising debt and equity necessary to fund its acquisitions and operations. As such, management has concluded that the Company can satisfy its obligations for at least the next twelve months from the issuance date of these financial statements.

The Company’s ability to access capital markets or to otherwise obtain sufficient financing may be affected by future conditions. If the Company is unable to execute its plan to refinance debt obligations, the Company’s credit facility could be terminated, and amounts due under its revolver and other borrowing arrangements could be declared immediately due and payable.

LIBOR

Certain rates established at LIBOR were scheduled to be discontinued after 2021 as part of reference rate reform, while other LIBOR-based rates are scheduled to be discontinued after June 2023. As of September 30, 2022, the Company had $1.009 billion in outstanding borrowings under Centuri’s term loan facility. Southwest, MountainWest, and Southwest Gas Holdings, Inc. had no outstanding borrowings or variable rate debt agreements with reference to LIBOR as of September 30, 2022.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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+ Details

Other Comprehensive Income and Accumulated Other Comprehensive Income

9 Months Ended

Sep. 30, 2022

Equity [Abstract]

Other Comprehensive Income and Accumulated Other Comprehensive Income

Note 6 – Other Comprehensive Income and Accumulated Other Comprehensive Income

The following information presents the Company’s Other comprehensive income (loss), both before and after-tax impacts, within the Condensed Consolidated Statements of Comprehensive Income, which also impact Accumulated other comprehensive income (“AOCI”) in the Condensed Consolidated Balance Sheets and the Condensed Consolidated Statements of Equity.

Related Tax Effects Allocated to Each Component of Other Comprehensive Income (Loss)


	Three Months Ended September 30, 2022						Three Months Ended September 30, 2021
(Thousands of dollars)	Before- Tax Amount		Tax (Expense) or Benefit (1)		Net-of- Tax Amount		Before- Tax Amount		Tax (Expense) or Benefit (1)		Net-of- Tax Amount
Defined benefit pension plans:
Amortization of prior service cost	$	44	$	(10)	$	34	$	239	$	(56)	$	183
Amortization of net actuarial (gain)/loss	8,705		(2,089)		6,616		11,151		(2,677)		8,474
Regulatory adjustment	(7,268)		1,744		(5,524)		(9,575)		2,298		(7,277)
Pension plans other comprehensive income (loss)	1,481		(355)		1,126		1,815		(435)		1,380
FSIRS (designated hedging activities):
Amounts reclassified into net income	—		—		—		544		(131)		413
FSIRS other comprehensive income (loss)	—		—		—		544		(131)		413
Total other comprehensive income (loss) - Southwest Gas Corporation	1,481		(355)		1,126		2,359		(566)		1,793
Foreign currency translation adjustments:
Translation adjustments	(5,830)		—		(5,830)		(2,056)		—		(2,056)
Foreign currency other comprehensive income (loss)	(5,830)		—		(5,830)		(2,056)		—		(2,056)
Total other comprehensive income (loss) - Southwest Gas Holdings, Inc.	$	(4,349)	$	(355)	$	(4,704)	$	303	$	(566)	$	(263)

	Nine Months Ended September 30, 2022						Nine Months Ended September 30, 2021
(Thousands of dollars)	Before- Tax Amount		Tax (Expense) or Benefit (1)		Net-of- Tax Amount		Before- Tax Amount		Tax (Expense) or Benefit (1)		Net-of- Tax Amount
Defined benefit pension plans:
Amortization of prior service cost	$	132	$	(32)	$	100	$	719	$	(172)	$	547
Amortization of net actuarial (gain)/loss	26,114		(6,267)		19,847		33,448		(8,028)		25,420
Regulatory adjustment	(21,804)		5,233		(16,571)		(28,725)		6,894		(21,831)
Pension plans other comprehensive income (loss)	4,442		(1,066)		3,376		5,442		(1,306)		4,136
FSIRS (designated hedging activities):
Amounts reclassified into net income	545		(129)		416		1,632		(392)		1,240
FSIRS other comprehensive income (loss)	545		(129)		416		1,632		(392)		1,240
Total other comprehensive income (loss) - Southwest Gas Corporation	4,987		(1,195)		3,792		7,074		(1,698)		5,376
Foreign currency translation adjustments:
Translation adjustments	(7,263)		—		(7,263)		(324)		—		(324)
Foreign currency other comprehensive income (loss)	(7,263)		—		(7,263)		(324)		—		(324)
Total other comprehensive income (loss) - Southwest Gas Holdings, Inc.	$	(2,276)	$	(1,195)	$	(3,471)	$	6,750	$	(1,698)	$	5,052


	Twelve Months Ended September 30, 2022						Twelve Months Ended September 30, 2021
(Thousands of dollars)	Before- Tax Amount		Tax (Expense) or Benefit (1)		Net-of- Tax Amount		Before- Tax Amount		Tax (Expense) or Benefit (1)		Net-of- Tax Amount
Defined benefit pension plans:
Net actuarial gain/(loss)	$	59,176	$	(14,202)	$	44,974	$	(57,539)	$	13,809	$	(43,730)
Amortization of prior service cost	372		(90)		282		1,007		(241)		766
Amortization of net actuarial (gain)/loss	37,263		(8,942)		28,321		42,906		(10,298)		32,608

Regulatory adjustment	(81,273)		19,506		(61,767)		3,894		(935)		2,959
Pension plans other comprehensive income (loss)	15,538		(3,728)		11,810		(9,732)		2,335		(7,397)
FSIRS (designated hedging activities):
Amounts reclassified into net income	1,087		(259)		828		2,176		(523)		1,653
FSIRS other comprehensive income (loss)	1,087		(259)		828		2,176		(523)		1,653
Total other comprehensive income (loss) - Southwest Gas Corporation	16,625		(3,987)		12,638		(7,556)		1,812		(5,744)
Foreign currency translation adjustments:
Translation adjustments	(6,919)		—		(6,919)		2,576		—		2,576
Foreign currency other comprehensive income (loss)	(6,919)		—		(6,919)		2,576		—		2,576
Total other comprehensive income (loss) - Southwest Gas Holdings, Inc.	$	9,706	$	(3,987)	$	5,719	$	(4,980)	$	1,812	$	(3,168)

(1)Tax amounts are calculated using a 24% rate. The Company has elected to indefinitely reinvest, in Canada, the earnings of Centuri’s Canadian subsidiaries, thus precluding deferred taxes on such earnings. As a result of this assertion, and no repatriation of earnings anticipated, the Company is not recognizing a tax effect or presenting a tax expense or benefit for currency translation adjustments reported in Other comprehensive income (loss).

The following table represents a rollforward of AOCI, presented on the Company’s Condensed Consolidated Balance Sheets and its Condensed Consolidated Statements of Equity:


	Defined Benefit Plans						FSIRS						Foreign Currency Items
(Thousands of dollars)	Before-Tax		Tax (Expense) Benefit (4)		After-Tax		Before-Tax		Tax (Expense) Benefit (4)		After-Tax		Before-Tax		Tax (Expense) Benefit		After-Tax		AOCI
Beginning Balance AOCI December 31, 2021	$	(61,182)	$	14,685	$	(46,497)	$	(545)	$	129	$	(416)	$	152	$	—	$	152	$	(46,761)
Translation adjustments	—		—		—		—		—		—		(7,263)		—		(7,263)		(7,263)
Other comprehensive income (loss) before reclassifications	—		—		—		—		—		—		(7,263)		—		(7,263)		(7,263)
FSIRS amount reclassified from AOCI (1)	—		—		—		545		(129)		416		—		—		—		416
Amortization of prior service cost (2)	132		(32)		100		—		—		—		—		—		—		100
Amortization of net actuarial loss (2)	26,114		(6,267)		19,847		—		—		—		—		—		—		19,847
Regulatory adjustment (3)	(21,804)		5,233		(16,571)		—		—		—		—		—		—		(16,571)
Net current period other comprehensive income (loss) attributable to Southwest Gas Holdings, Inc.	4,442		(1,066)		3,376		545		(129)		416		(7,263)		—		(7,263)		(3,471)
Ending Balance AOCI September 30, 2022	$	(56,740)	$	13,619	$	(43,121)	$	—	$	—	$	—	$	(7,111)	$	—	$	(7,111)	$	(50,232)

(1)The FSIRS reclassification amount is included in Net interest deductions on the Company’s Condensed Consolidated Statements of Income.

(2)These AOCI components are included in the computation of net periodic benefit cost (see Note 2 – Components of Net Periodic Benefit Cost for additional details).

(3)The regulatory adjustment represents the portion of the activity above that is expected to be recovered through rates in the future (the related regulatory asset is included in Deferred charges and other assets on the Company’s Condensed Consolidated Balance Sheets).

(4)Tax amounts are calculated using a 24% rate.

The following table represents a rollforward of AOCI, presented on Southwest’s Condensed Consolidated Balance Sheets:


	Defined Benefit Plans						FSIRS
(Thousands of dollars)	Before-Tax		Tax (Expense) Benefit (8)		After-Tax		Before-Tax		Tax (Expense) Benefit (8)		After-Tax		AOCI
Beginning Balance AOCI December 31, 2021	$	(61,182)	$	14,685	$	(46,497)	$	(545)	$	129	$	(416)	$	(46,913)
FSIRS amount reclassified from AOCI (5)	—		—		—		545		(129)		416		416
Amortization of prior service cost (6)	132		(32)		100		—		—		—		100
Amortization of net actuarial loss (6)	26,114		(6,267)		19,847		—		—		—		19,847
Regulatory adjustment (7)	(21,804)		5,233		(16,571)		—		—		—		(16,571)
Net current period other comprehensive income attributable to Southwest Gas Corporation	4,442		(1,066)		3,376		545		(129)		416		3,792
Ending Balance AOCI September 30, 2022	$	(56,740)	$	13,619	$	(43,121)	$	—	$	—	$	—	$	(43,121)

(5) The FSIRS reclassification amount is included in Net interest deductions on Southwest’s Condensed Consolidated Statements of Income.

(6)These AOCI components are included in the computation of net periodic benefit cost (see Note 2 – Components of Net Periodic Benefit Cost for additional details).

(7)The regulatory adjustment represents the portion of the activity above that is expected to be recovered through rates in the future (the related regulatory asset is included in Deferred charges and other assets on Southwest’s Condensed Consolidated Balance Sheets).

(8)Tax amounts are calculated using a 24% rate.

The following table represents amounts (before income tax impacts) included in AOCI (in the tables above), that have not yet been recognized in net periodic benefit cost:


(Thousands of dollars)	September 30, 2022		December 31, 2021
Net actuarial loss	$	(372,896)	$	(399,010)
Prior service cost	(1,396)		(1,528)
Less: amount recognized in regulatory assets	317,552		339,356
Recognized in AOCI	$	(56,740)	$	(61,182)

Segment Information

9 Months Ended

Sep. 30, 2022

Segment Reporting [Abstract]

Segment Information

Note 7 – Segment Information

As a result of the MountainWest acquisition on December 31, 2021, management updated its segment reporting from the historical presentation of two reportable segments to three reportable segments, with MountainWest presented as the pipeline and storage segment. Southwest comprises the natural gas distribution segment and Centuri comprises the utility infrastructure services segment.

Centuri accounts for services provided to Southwest at contractual prices. Accounts receivable for these services, which are not eliminated during consolidation, are presented in the table below:


(Thousands of dollars)	September 30, 2022		December 31, 2021
Centuri accounts receivable for services provided to Southwest	$	14,393	$	15,166

In order to reconcile (below) to net income (loss) as disclosed in the Condensed Consolidated Statements of Income, an Other column is included associated with impacts of corporate and administrative activities related to Southwest Gas Holdings, Inc. The financial information pertaining to the natural gas distribution, utility infrastructure services, and pipeline and storage segments are as follows:


(Thousands of dollars)	Natural Gas Distribution		Utility Infrastructure Services		Pipeline and Storage		Other		Total
Three Months Ended September 30, 2022
Revenues from external customers	$	303,944	$	721,910	$	63,178	$	—	$	1,089,032
Intersegment revenues	—		36,556		—		—		36,556
Total	$	303,944	$	758,466	$	63,178	$	—	$	1,125,588
Segment net income (loss)	$	(22,199)	$	14,345	$	12,320	$	(16,775)	$	(12,309)

Three Months Ended September 30, 2021
Revenues from external customers	$	255,848	$	606,006	$	—	$	—	$	861,854
Intersegment revenues	—		26,842		—		—		26,842
Total	$	255,848	$	632,848	$	—	$	—	$	888,696
Segment net income (loss)	$	(27,544)	$	18,540	$	—	$	(2,572)	$	(11,576)

(Thousands of dollars)	Natural Gas Operations		Utility Infrastructure Services		Pipeline and Storage		Other		Total
Nine Months Ended September 30, 2022
Revenues from external customers	$	1,358,425	$	1,889,573	$	192,259	$	—	$	3,440,257
Intersegment revenues	—		98,860		—		—		98,860
Total	$	1,358,425	$	1,988,433	$	192,259	$	—	$	3,539,117
Segment net income (loss)	$	87,330	$	(4,400)	$	44,326	$	(49,962)	$	77,294

Nine Months Ended September 30, 2021
Revenues from external customers	$	1,070,576	$	1,450,719	$	—	$	—	$	2,521,295
Intersegment revenues	—		74,729		—		—		74,729
Total	$	1,070,576	$	1,525,448	$	—	$	—	$	2,596,024
Segment net income (loss)	$	102,584	$	32,797	$	—	$	(4,545)	$	130,836


(Thousands of dollars)	Natural Gas Distribution		Utility Infrastructure Services		Pipeline and Storage		Other		Total
Twelve Months Ended September 30, 2022
Revenues from external customers	$	1,809,639	$	2,495,169	$	192,259	$	—	$	4,497,067
Intersegment revenues	—		126,477		—		—		126,477
Total	$	1,809,639	$	2,621,646	$	192,259	$	—	$	4,623,544
Segment net income (loss)	$	171,881	$	3,223	$	44,326	$	(72,193)	$	147,237

Twelve Months Ended September 30, 2021
Revenues from external customers	$	1,445,066	$	1,957,667	$	—	$	—	$	3,402,733
Intersegment revenues	—		107,371		—		—		107,371
Total	$	1,445,066	$	2,065,038	$	—	$	—	$	3,510,104
Segment net income (loss)	$	182,134	$	56,723	$	—	$	(4,477)	$	234,380

The corporate and administrative activities for Southwest Gas Holdings, Inc. in the three-, nine-, and twelve-month periods ended September 30, 2022 include expenses incurred related to shareholder activism and related settlement activities, expenses incurred in conducting the Strategic Review, and expenses and financing costs for the MountainWest acquisition.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8924-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 34
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8981-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8721-108599

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 40
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e9031-108599

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (f)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8844-108599

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
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-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e9038-108599

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e9054-108599

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8657-108599

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
-Paragraph 21
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-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8721-108599

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-URI https://asc.fasb.org/topic&trid=2134510

+ Details

Business Acquisitions

9 Months Ended

Sep. 30, 2022

Business Combination and Asset Acquisition [Abstract]

Business Acquisitions

Note 8 - Business Acquisitions

In August 2021, the Company, through its subsidiaries, led principally by Centuri, completed the acquisition of Drum, including its primary subsidiary, Riggs Distler. In November 2021, certain members of Riggs Distler management acquired a 1.42% interest in Drum. See the Company’s 2021 Form 10-K for additional information about this acquisition.

Assets acquired and liabilities assumed in the transaction were recorded at their acquisition date fair values. Transaction costs associated with the acquisition were expensed as incurred. The Company’s allocation of the purchase price was based on an evaluation of the appropriate fair values and represented management’s best estimate based on available data (including market data, data regarding customers of the acquired businesses, terms of acquisition-related agreements, analysis of historical and projected results, and other types of data). The analysis included consideration of types of intangibles that were acquired, including customer relationships, trade name, and backlog. Certain payments were estimated as of the acquisition date and were adjusted when amounts were finalized.

The final estimated fair values of assets acquired and liabilities assumed as of August 27, 2021, and as updated through August 27, 2022, are as follows:


(Millions of dollars)	Acquisition Date		Measurement Period Adjustments		Revised Acquisition Date
Cash and cash equivalents	$	1.9	$	—	$	1.9
Accounts receivable	69.1		(8.6)		60.5
Contract assets	40.1		7.4		47.5
Income taxes receivable, net	0.7		(0.3)		0.4
Right of use assets under operating leases	1.5		—		1.5
Prepaid expenses	5.2		—		5.2
Property and equipment	118.1		1.2		119.3
Intangible assets	335.0		(31.5)		303.5
Goodwill	446.8		0.8		447.6
Total assets acquired	1,018.4		(31.0)		987.4

Trade and other payables	46.2		—		46.2
Finance lease obligations	27.5		1.2		28.7
Contract liabilities	12.7		0.1		12.8
Operating lease obligations	1.5		—		1.5
Other liabilities	5.3		(1.2)		4.1
Deferred tax liabilities	94.8		(24.8)		70.0
Total liabilities assumed and noncontrolling interest	188.0		(24.7)		163.3
Net assets acquired	$	830.4	$	(6.3)	$	824.1

The Company incurred and expensed acquisition costs of $14 million, included in Utility infrastructure services expenses in the Company’s Condensed Consolidated Statement of Income for the twelve months ended September 30, 2022. No acquisition-related costs were incurred during the three and nine months ended September 30, 2022, and no significant impacts to earnings resulted from the measurement-period adjustments reflected above.

In December 2021, Southwest Gas Holdings, Inc. completed the acquisition of Dominion Energy Questar Pipeline, LLC and related entities (subsequently rebranded as “MountainWest”), which resulted in MountainWest becoming a wholly owned subsidiary of the Company. See the Company’s 2021 Form 10-K for additional information about this acquisition.

Assets acquired and liabilities assumed in the transaction were recorded at their acquisition date fair values. Transaction costs associated with the acquisition were expensed as incurred. The majority of the operations acquired are subject to FERC rate-regulation and therefore are accounted for pursuant to ASC 980, Regulated Operations. The fair values of MountainWest’s assets and liabilities, subject to rate making and cost recovery provisions, provide revenues derived from costs of service, including a return on investment of assets and liabilities included in rate base. Accordingly, the carrying values of such assets

and liabilities were deemed to approximate their fair values. The fair value of the MountainWest assets and liabilities assumed that are not subject to the rate-regulation provisions discussed above include a 50% equity method investment, non-regulated property, plant and equipment, and long-term debt assumed; related fair values were determined using a market approach, income approach, or cost approach, as appropriate. Amounts related to post-closing payments and deferred taxes were estimated as of the acquisition date and adjusted when determined during the period ended September 30, 2022. No other measurement period adjustments occurred during the period. However, the final purchase accounting has not yet been completed and further refinements may occur.

The estimated fair values of assets acquired and liabilities assumed as of December 31, 2021, as updated through September 30, 2022, are as follows:


(Millions of dollars)	Acquisition Date		Measurement Period Adjustments		Revised Acquisition Date
Gas plant, net	$	1,047.4	$	—	$	1,047.4
Other property and investments	51.3		—		51.3
Cash and cash equivalents	17.6		—		17.6
Accounts receivable, net of allowances	26.6		2.9		29.5
Prepaid and other current assets	27.4		—		27.4
Deferred charges and other assets	31.1		—		31.1
Goodwill	986.2		(28.2)		958.0
Deferred income taxes, net	15.4		20.9		36.3
Total assets acquired	2,203.0		(4.4)		2,198.6

Long-term debt	449.7		—		449.7
Accounts payable	7.0		—		7.0
Deferred purchased gas costs	5.7		—		5.7
Customer deposits	3.2		—		3.2
Accrued general taxes	0.4		—		0.4
Accrued interest	4.7		—		4.7
Other current liabilities	14.5		—		14.5
Accumulated removal costs	56.6		—		56.6
Other deferred credits	85.6		—		85.6
Total liabilities assumed	627.4		—		627.4
Net assets acquired	$	1,575.6	$	(4.4)	$	1,571.2

The Company incurred and expensed acquisition costs of $18.5 million for the twelve months ended September 30, 2022, which are included in Operations and maintenance expense on the Company’s Condensed Consolidated Statement of Income. No acquisition-related costs were incurred during the nine months ended September 30, 2022 and no impacts to earnings resulted from the measurement-period adjustments reflected above. The Company has a transition services agreement with the sellers for a period of up to twelve months from the acquisition date of December 31, 2021, to continue certain corporate and administrative functions for the entities acquired while MountainWest is established as an independent enterprise. The Company currently expects that a limited number of activities under the transition services agreement will be extended, and of those extended, certain will occur through the second quarter of 2023

Subsequent Events	9 Months Ended
Subsequent Events	Sep. 30, 2022
Subsequent Events [Abstract]
Subsequent Events	Note 9 - Subsequent Events On October 24, 2022, the Company and the Icahn Group entered into the Amended Cooperation Agreement, which amended, restated, superseded, and replaced in its entirety the Initial Cooperation Agreement. In accordance with the terms of the Amended Cooperation Agreement, the Company agreed with the Icahn Group, among other things, to nominate each of Andrew W. Evans, Henry P. Linginfelter, Ruby Sharma, and Andrew J. Teno (each, an “Icahn Designee” and, collectively, the “Icahn Designees”) for election at the Company’s 2023 annual meeting of stockholders (the “2023 Annual Meeting”). In addition, subject to qualifications set forth in the Amended Cooperation Agreement, the Amended Cooperation Agreement provides that the standstill restrictions on the Icahn Group will remain in effect until, and the Amended Cooperation Agreement will terminate upon, the later of (x) the conclusion of the 2023 Annual Meeting and (y) the earlier of (1) immediately following the time at which Andrew J. Teno (or any Replacement Designee for Mr. Teno, as such term is defined in the Amended Cooperation Agreement) is no longer serving on the Board and (2) thirty (30) days prior to the expiration of the advance notice deadline for the submission of director nominees in connection with the Company’s 2024 Annual Meeting of Stockholders (as such term is defined in the Amended Cooperation Agreement); provided, however, that the Amended Cooperation Agreement will terminate automatically on the date on which the Board re-appoints as a director any former director of the Board (i.e., any person who was a director of the Board prior to the 2022 Annual Meeting, but was not a director of the Board immediately after the 2022 Annual Meeting), without the approval of a majority of the Icahn Designees. Pursuant to the terms of the Amended Cooperation Agreement, the Company further agreed with the Icahn Group (i) to maintain one-year terms and annual elections for all directors serving on the Board through the term of the Amended Cooperation Agreement, (ii) to establish the record date for the 2023 Annual Meeting for a time within thirty (30) days of March 21, 2023, and (iii) that in the event that the Strategic Transactions Committee approves any separation of the Company’s businesses into two or more independent, publicly traded companies (any such separation, a “Spinoff” and each such resulting independent, publicly traded company, a “SpinCo”) during the term of the Amended Cooperation Agreement and while Icahn Group owns a Net Long Position of a number of shares of Common Stock that is at least 50% of the Tender Offer Closing Amount (each such term, as defined in the Amended Cooperation Agreement), any such SpinCo will be organized in Delaware, any such SpinCo’s board of directors will be annually elected for one-year terms and the first meeting of stockholders for such SpinCo will be held no earlier than the nine-month anniversary of the consummation of the Spinoff and no later than the twelve-month anniversary of the Spinoff, subject to certain exceptions set forth in the Amended Cooperation Agreement. Additionally, on November 4, 2022, Centuri amended the financial covenants of its revolving credit facility to increase the maximum total net leverage ratio during the period from December 31, 2022 through December 31, 2023 (the “Credit Facility Amendment”). The Credit Facility Amendment also transitioned the interest rate benchmark for the revolving credit facility from LIBOR to SOFR. The applicable margin for the revolving credit facility now ranges from 1.0% to 2.5% for SOFR loans and from 0.0% to 1.5% for CDOR and “base rate” loans, depending on Centuri’s total net leverage ratio. Further, the Credit Facility Amendment increases a letter of credit sub-facility from $100 million to $125 million. The Credit Facility Amendment did not modify any terms of the term loan facility.

Background, Organization, and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations	Nature of Operations. Southwest Gas Holdings, Inc. (together with its subsidiaries, the “Company”) is a holding company, owning all of the shares of common stock of Southwest Gas Corporation (“Southwest” or the “natural gas distribution” segment), all of the shares of common stock of Centuri Group, Inc. (“Centuri,” or the “utility infrastructure services” segment), and all of the shares of common stock of MountainWest Pipelines Holding Company (“MountainWest,” or the “pipeline and storage” segment). Southwest is engaged in the business of purchasing, distributing, and transporting natural gas for customers in portions of Arizona, Nevada, and California. Public utility rates, practices, facilities, and service territories of Southwest are subject to regulatory oversight. The timing and amount of rate relief can materially impact results of operations. Natural gas purchases and the timing of related recoveries can materially impact liquidity. Results for the natural gas distribution segment are higher during winter periods due to the seasonality incorporated in its regulatory rate structures. The Company completed the acquisition of Dominion Energy Questar Pipeline, LLC and related entities (“Questar Pipelines”) in December 2021 and formed MountainWest, which owns all of the membership interests in Questar Pipelines. In April 2022, the Company completed a general rebranding of the Questar Pipelines entities under the MountainWest name. The acquired operations further diversify the Company’s business in the midstream sector, with an expansion of interstate natural gas pipelines and underground storage services, primarily composed of regulated operations under the jurisdiction of the Federal Energy Regulatory Commission (the “FERC”), thereby expanding natural gas transportation services into Utah, Wyoming, and Colorado. See Note 8 - Business Acquisitions for more information. Centuri is a strategic utility infrastructure services company dedicated to partnering with North America’s gas and electric providers to build and maintain the energy network that powers millions of homes across the United States (“U.S.”) and Canada. Centuri derives revenue primarily from installation, replacement, repair, and maintenance of energy networks. Centuri operates in the U.S., primarily as NPL, Neuco, Linetec, and Riggs Distler, and in Canada, primarily as NPL Canada. Utility infrastructure services activity is seasonal in many of Centuri’s operating areas. Peak periods are the summer and fall months in colder climate areas, such as the northeastern and midwestern U.S. and in Canada. In warmer climate areas, such as the southwestern and southeastern U.S., utility infrastructure services activity continues year round.
Basis of Presentation	Basis of Presentation. The condensed consolidated financial statements of Southwest Gas Holdings, Inc. and subsidiaries and Southwest (with its subsidiaries) included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). The year-end 2021 condensed balance sheet data was derived from audited financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) have been condensed or omitted pursuant to such rules and regulations. No substantive change has occurred with regard to the Company’s business segments on the whole during the recently completed quarter. The preparation of the condensed consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. In the opinion of management, all adjustments, consisting of normal recurring items and estimates necessary for a fair depiction of results for the interim periods, have been made. These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in the 2021 Annual Report to Stockholders, which is incorporated by reference into the 2021 Form 10-K.
Cash and Cash Equivalents	Cash and Cash Equivalents. Cash and cash equivalents of the Company include $56 million and $20 million of money market fund investments at September 30, 2022 and December 31, 2021, respectively. The money market fund investments for Southwest were insignificant at both balance sheet dates. These investments fall within Level 2 of the fair value hierarchy, due to the asset valuation methods used by money market funds. Noncash investing activities for the Company and Southwest include capital expenditures that were not yet paid, thereby remaining in accounts payable, the amounts related to which declined by approximately $4.8 million and $11.6 million during the nine months ended September 30, 2022, respectively, and increased $16.1 million and $9.4 million during the twelve months ended September 30, 2022, respectively.
Accounts Receivable, net of allowances	Accounts Receivable, net of allowances. Following an earlier moratorium on account disconnections amidst the COVID-19 environment, account collection efforts resumed in 2021 in all jurisdictions in which Southwest operates. Ultimately, some accounts may not be collected, and if collection is unsuccessful, such accounts are written off. Estimates as to collectibility are made on an ongoing basis. However, Southwest continues to actively work with customers experiencing financial hardship by means of flexible payment options and partnering with assistance agencies. The cost of gas included in customer rates also influences account balances at each reporting date.
Deferred Purchased Gas Costs	Deferred Purchased Gas Costs. The various regulatory commissions have established procedures to enable the rate-regulated companies to adjust billing rates for changes in the cost of natural gas purchased. The difference between the current cost of gas purchased and the cost of gas recovered in billed rates is deferred. Generally, these deferred amounts are recovered or refunded within one year.
Prepaid and other current assets	Prepaid and other current assets. Prepaid and other current assets for Southwest include, among other things, materials and operating supplies of $76.5 million at September 30, 2022 and $62.9 million at December 31, 2021 (carried at weighted average cost). For the Company, there were materials and operating supplies of $80.8 million and $67.4 million at September 30, 2022 and December 31, 2021, respectively, which included amounts for MountainWest. Also included in the balance for both Southwest and the Company was $15.5 million and $51.6 million as of September 30, 2022 and December 31, 2021, respectively, in accrued purchased gas cost.
Goodwill	Goodwill. Goodwill is assessed as of October 1st each year for impairment, or more frequently, if circumstances indicate it may be more likely than not that the fair value of a reporting unit is less than its carrying value. The Company’s reporting units for goodwill are its operating segments, which are also its reportable segments. The acquisition of MountainWest resulted in a new reportable segment, which was assessed for impairment for the first time in 2022.
Other Current Liabilities	Other Current Liabilities. Management recognizes in its balance sheets various liabilities that are expected to be settled through future cash payment within the next twelve months, including amounts payable under regulatory mechanisms, customary accrued expenses for employee compensation and benefits, declared but unpaid dividends, and miscellaneous other accrued liabilities. Other current liabilities for the Company include $41.6 million and $36 million of dividends declared as of September 30, 2022 and December 31, 2021, respectively.
Earnings Per Share	Earnings Per Share. Basic earnings per share (“EPS”) in each period of this report were calculated by dividing net income attributable to Southwest Gas Holdings, Inc. by the weighted-average number of shares during those periods. Diluted EPS includes additional weighted-average common stock equivalents (performance shares and restricted stock units). Unless otherwise noted, the term “Earnings Per Share” refers to Basic EPS.
Recent Accounting Standards Updates	Recent Accounting Standards Updates. Accounting pronouncements effective or adopted in 2022: In March 2020, the Financial Accounting Standards Board (the “FASB”) issued ASU 2020-04 “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting.” The update provides optional guidance for a limited time to ease the potential burden in accounting for, or recognizing the effects of, reference rate reform on financial reporting, including when modifying a contract (during the eligibility period covered by the update to Topic 848) to replace a reference rate affected by such reform. The update applies only to contracts and hedging relationships that reference the London Interbank Offered Rate (“LIBOR”) or another rate expected to be discontinued due to reference rate reform. The guidance was eligible to be applied upon issuance on March 12, 2020, and can generally be applied through December 31, 2022, and while a proposal by the FASB has occurred to extend the optional guidance to the full tenor of LIBOR expiration dates occurring after 2022, to date, no such update has been made effective. Management will monitor the impacts this update might have on the Company’s and Southwest’s consolidated financial statements and disclosures, and will reflect such appropriately, in the event that the optional guidance is elected. Management will also monitor further FASB action, if any, in regard to the full tenor of LIBOR expiration dates. In August 2020, the FASB issued ASU 2020-06 “Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging— Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity.” The update, amongst other amendments, improves the guidance related to the disclosures and earnings-per-share for convertible instruments and contracts in an entity’s own equity. The Company and Southwest adopted the update in the first quarter of 2022, the impact of which was not material to the consolidated financial statements of the Company or Southwest.

Background, Organization, and Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2022

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Other Property and Investments

Other property and investments on Southwest’s and the Company’s Condensed Consolidated Balance Sheets includes:


(Thousands of dollars)	September 30, 2022		December 31, 2021
Net cash surrender value of COLI policies	$	141,705	$	149,947
Other property	3,856		3,146
Total Southwest Gas Corporation	145,561		153,093
Non-regulated property, equipment, and intangibles	1,704,354		1,616,392
Non-regulated accumulated provision for depreciation and amortization	(595,393)		(512,343)
Other property and investments	56,812		59,337
Total Southwest Gas Holdings, Inc.	$	1,311,334	$	1,316,479

Schedule of Goodwill

Goodwill in the Natural Gas Distribution operations of Southwest, and across all operations of the Company, is included in their respective Condensed Consolidated Balance Sheets as follows:


(Thousands of dollars)	Natural Gas Distribution		Utility Infrastructure Services		Pipeline and Storage		Total Company
December 31, 2021	$	10,095	$	785,058	$	986,179	$	1,781,332
Measurement-period adjustments from Riggs Distler acquisition (a)	—		(1,924)		—		(1,924)
Measurement-period adjustments from MountainWest acquisition (a)	—		—		(28,177)		(28,177)
Foreign currency translation adjustment	—		(8,264)		—		(8,264)
September 30, 2022	$	10,095	$	774,870	$	958,002	$	1,742,967

(a) See Note 8 - Business Acquisitions for details regarding measurement-period adjustments.

Schedule of Significant Items Included in Other Income (Deductions)

The following table provides the composition of significant items included in Other income (deductions) in Southwest’s and the Company’s Condensed Consolidated Statements of Income:


	Three Months Ended September 30,				Nine Months Ended September 30,				Twelve Months Ended September 30,
(Thousands of dollars)	2022		2021		2022		2021		2022		2021
Southwest Gas Corporation:
Change in COLI policies	$	(1,500)	$	—	$	(8,700)	$	5,800	$	(5,700)	$	14,000
Interest income	4,356		1,365		10,355		3,312		12,156		4,113
Equity AFUDC	91		—		248		—		248		1,311
Other components of net periodic benefit cost	(188)		(3,506)		(563)		(10,516)		(4,068)		(15,522)
Miscellaneous income and (expense)	(1,081)		(2,146)		(1,780)		(3,498)		(2,733)		(4,447)
Southwest Gas Corporation - total other income (deductions)	1,678		(4,287)		(440)		(4,902)		(97)		(545)
Centuri, MountainWest, and Southwest Gas Holdings, Inc.:

Foreign transaction gain (loss)	(182)		(7)		35		(19)		32		(19)
Equity AFUDC	246		—		664		—		664		—
Equity in earnings of unconsolidated investments	624		67		1,867		168		1,925		159
Miscellaneous income and (expense)	(773)		1,115		(2,124)		778		(2,046)		687
Southwest Gas Holdings, Inc. - total other income (deductions)	$	1,593	$	(3,112)	$	2	$	(3,975)	$	478	$	282

Summary of Redeemable Noncontrolling Interest

The following depicts changes to the balances of the redeemable noncontrolling interests:


(Thousands of dollars):	Linetec		Drum		Total
Balance, December 31, 2021	$	184,148	$	12,569	$	196,717
Net income (loss) attributable to redeemable noncontrolling interests	2,582		(25)		2,557
Redemption value adjustments	(44,933)		—		(44,933)
Redemption of equity interest from noncontrolling party	(39,649)		—		(39,649)
Balance, September 30, 2022	$	102,148	$	12,544	$	114,692

Schedule of Earnings Per Share, Basic and Diluted

A reconciliation of the denominator used in Basic and Diluted EPS calculations is shown in the following table:


	Three Months Ended September 30,		Nine Months Ended September 30,		Twelve Months Ended September 30,
(In thousands)	2022	2021	2022	2021	2022	2021
Weighted average basic shares	67,157	59,688	65,004	58,639	63,905	58,209
Effect of dilutive securities:
Restricted stock units (1)	168	128	144	103	146	103
Weighted average diluted shares	67,325	59,816	65,148	58,742	64,051	58,312

- Definition

Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
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-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
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-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Topic 350
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-Section 50
-Paragraph 1
-Subparagraph (e)
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Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13854-109267

Reference 11: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 55
-Paragraph 24
-URI https://asc.fasb.org/extlink&oid=122137925&loc=d3e14258-109268

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Paragraph 1
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

+ Details

Components of Net Periodic Benefit Cost (Tables)

9 Months Ended

Sep. 30, 2022

Retirement Benefits [Abstract]

Schedule of Net Periodic Benefit Costs


	Qualified Retirement Plan
	September 30,
	Three Months				Nine Months				Twelve Months
	2022		2021		2022		2021		2022		2021
(Thousands of dollars)
Service cost	$	11,028	$	10,289	$	33,084	$	30,869	$	43,374	$	39,443
Interest cost	11,251		10,108		33,753		30,324		43,861		41,714
Expected return on plan assets	(19,978)		(18,088)		(59,934)		(54,264)		(78,022)		(70,588)
Amortization of net actuarial loss	8,117		10,489		24,351		31,467		34,839		40,473
Net periodic benefit cost	$	10,418	$	12,798	$	31,254	$	38,396	$	44,052	$	51,042

	SERP
	September 30,
	Three Months				Nine Months				Twelve Months
	2022		2021		2022		2021		2022		2021
(Thousands of dollars)
Service cost	$	106	$	131	$	318	$	394	$	450	$	491
Interest cost	360		358		1,080		1,074		1,437		1,474
Amortization of net actuarial loss	588		661		1,763		1,981		2,424		2,433
Net periodic benefit cost	$	1,054	$	1,150	$	3,161	$	3,449	$	4,311	$	4,398

	PBOP
	September 30,
	Three Months				Nine Months				Twelve Months
	2022		2021		2022		2021		2022		2021
(Thousands of dollars)
Service cost	$	485	$	423	$	1,455	$	1,269	$	1,877	$	1,664
Interest cost	613		549		1,839		1,645		2,387		2,291
Expected return on plan assets	(807)		(810)		(2,421)		(2,430)		(3,230)		(3,282)
Amortization of prior service costs	44		239		132		719		372		1,007

Net periodic benefit cost	$	335	$	401	$	1,005	$	1,203	$	1,406	$	1,680

Revenue (Tables)

9 Months Ended

Sep. 30, 2022

Revenue from Contract with Customer [Abstract]

Summary of Revenue Disaggregated by Service Type and Contract Type


	Three Months Ended September 30,				Nine Months Ended September 30,				Twelve Months Ended September 30,
(Thousands of dollars)	2022		2021		2022		2021		2022		2021
Residential	$	170,196	$	147,326	$	913,355	$	743,791	$	1,205,176	$	1,011,450
Small commercial	61,780		48,283		264,494		185,774		348,934		248,193
Large commercial	19,590		14,199		60,740		40,030		78,081		52,075
Industrial/other	13,319		9,608		34,064		30,352		46,025		37,505
Transportation	22,936		21,884		74,034		68,217		98,057		91,151
Revenue from contracts with customers	287,821		241,300		1,346,687		1,068,164		1,776,273		1,440,374
Alternative revenue program revenues (deferrals)	13,609		12,569		1,132		(5,335)		19,648		(2,740)
Other revenues (1)	2,514		1,979		10,606		7,747		13,718		7,432
Total Regulated operations revenues	$	303,944	$	255,848	$	1,358,425	$	1,070,576	$	1,809,639	$	1,445,066


	Three Months Ended September 30,				Nine Months Ended September 30,				Twelve Months Ended September 30,
(Thousands of dollars)	2022		2021		2022		2021		2022		2021
Service Types:
Gas infrastructure services	$	467,751	$	393,122	$	1,147,302	$	961,836	$	1,487,806	$	1,287,552
Electric power infrastructure services	189,209		155,456		550,926		347,061		729,067		475,895
Other	101,506		84,270		290,205		216,551		404,773		301,591
Total Utility infrastructure services revenues	$	758,466	$	632,848	$	1,988,433	$	1,525,448	$	2,621,646	$	2,065,038


	Three Months Ended September 30,				Nine Months Ended September 30,				Twelve Months Ended September 30,
(Thousands of dollars)	2022		2021		2022		2021		2022		2021
Contract Types:
Master services agreement	$	637,582	$	467,869	$	1,700,416	$	1,160,199	$	2,193,195	$	1,573,247
Bid contract	120,884		164,979		288,017		365,249		428,451		491,791
Total Utility infrastructure services revenues	$	758,466	$	632,848	$	1,988,433	$	1,525,448	$	2,621,646	$	2,065,038

Unit price contracts	$	453,718	$	406,404	$	1,178,168	$	1,002,779	$	1,544,471	$	1,373,746
Fixed price contracts	117,983		64,632		333,313		149,681		451,374		197,447
Time and materials contracts	186,765		161,812		476,952		372,988		625,801		493,845
Total Utility infrastructure services revenues	$	758,466	$	632,848	$	1,988,433	$	1,525,448	$	2,621,646	$	2,065,038


	Three Months Ended September 30,		Nine Months Ended September 30,
(Thousands of dollars)	2022
Regulated gas transportation and storage revenues	$	59,283	$	179,046
NGL revenues	1,469		4,838
Other revenues	2,385		8,244
Revenue from contracts with customers	63,137		192,128
Other revenues	41		131
Total Regulated operations revenues	$	63,178	$	192,259

Summary of Information about Receivables, Revenue Earned on Contracts in Progress in Excess of Billings, Which are Included Within Accounts Receivable, Net of Allowances, and Amounts Billed in Excess of Revenue Earned on Contracts


(Thousands of dollars)	September 30, 2022		December 31, 2021
Contracts receivable, net	$	398,345	$	296,005
Revenue earned on contracts in progress in excess of billings	253,966		214,774
Amounts billed in excess of revenue earned on contracts	31,877		11,860

Schedule of Utility Infrastructure Services Contracts Receivable

Utility infrastructure services contracts receivable consists of the following:


(Thousands of dollars)	September 30, 2022		December 31, 2021
Billed on completed contracts and contracts in progress	$	400,831	$	292,770
Other receivables	1,885		3,492
Contracts receivable, gross	402,716		296,262
Allowance for doubtful accounts	(4,371)		(257)
Contracts receivable, net	$	398,345	$	296,005

Common Stock (Tables)

9 Months Ended

Sep. 30, 2022

Equity [Abstract]

Schedule of Common Stock Activity

The following table provides the life-to-date activity under that program through September 30, 2022:




Gross proceeds	$	158,180,343
Less: agent commissions	(1,581,803)
Net proceeds	$	156,598,540
Number of shares sold	2,302,407
Weighted average price per share	$	68.70

Debt (Tables)

9 Months Ended

Sep. 30, 2022

Debt Disclosure [Abstract]

Schedule of Carrying Amounts and Estimated Fair Values of Long-Term Debt

Details surrounding the fair value and individual carrying values of instruments are provided in the table that follows.


	September 30, 2022				December 31, 2021
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
(Thousands of dollars)
Southwest Gas Corporation:
Debentures:
Notes, 6.1%, due 2041	$	125,000	$	113,398	$	125,000	$	166,380
Notes, 4.05%, due 2032	600,000		506,346		—		—
Notes, 3.875%, due 2022	—		—		250,000		250,603
Notes, 4.875%, due 2043	250,000		202,383		250,000		307,538
Notes, 3.8%, due 2046	300,000		203,559		300,000		329,055
Notes, 3.7%, due 2028	300,000		267,903		300,000		325,191
Notes, 4.15%, due 2049	300,000		213,972		300,000		342,030
Notes, 2.2%, due 2030	450,000		340,763		450,000		440,838
Notes, 3.18%, due 2051	300,000		182,976		300,000		292,116
8% Series, due 2026	75,000		80,108		75,000		92,623
Medium-term notes, 7.78% series, due 2022	—		—		25,000		25,122
Medium-term notes, 7.92% series, due 2027	25,000		26,413		25,000		31,555
Medium-term notes, 6.76% series, due 2027	7,500		7,494		7,500		8,949
Unamortized discount and debt issuance costs	(26,701)				(19,959)
	2,705,799				2,387,541
Revolving credit facility and commercial paper	138,000		138,000		130,000		130,000
Industrial development revenue bonds:
Tax-exempt Series A, due 2028	50,000		50,000		50,000		50,000
2003 Series A, due 2038	50,000		50,000		50,000		50,000
2008 Series A, due 2038	50,000		50,000		50,000		50,000
2009 Series A, due 2039	50,000		50,000		50,000		50,000
Unamortized discount and debt issuance costs	(1,717)				(1,938)
	198,283				198,062
Less: current maturities	—				(275,000)
Southwest Gas Corporation total long-term debt, less current maturities	$	3,042,082			$	2,440,603
Southwest Gas Holdings, Inc.:
SWH term loan facility	$	1,147,747	1,148,057		$	—	$	—
Centuri secured term loan facility	1,008,550		977,033		1,117,138		1,117,841
Centuri secured revolving credit facility	150,571		150,740		103,329		103,749
MountainWest unsecured senior notes, 3.53%, due in 2028	101,843		86,345		102,078		102,078
MountainWest unsecured senior notes, 4.875%, due in 2041	199,431		152,581		199,926		199,926
MountainWest unsecured senior notes, 3.91%, due in 2038	147,812		103,398		147,735		147,735
Other debt obligations	134,274		122,980		51,665		50,003
Unamortized discount and debt issuance costs	(25,234)				(24,466)
Less: current maturities	(41,485)				(22,324)
Southwest Gas Holdings, Inc. total long-term debt, less current maturities	$	5,865,591			$	4,115,684

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e24072-122690

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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-Section 45
-Paragraph 1A
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28541-108399

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 5: http://www.xbrl.org/2003/role/exampleRef
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-Name Accounting Standards Codification
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Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 7: http://www.xbrl.org/2003/role/exampleRef
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Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21538-112644

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

Reference 11: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI https://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21475-112644

+ Details

Other Comprehensive Income and Accumulated Other Comprehensive Income (Tables)

9 Months Ended

Sep. 30, 2022

Equity [Abstract]

Related Tax Effects Allocated to Each Component of Other Comprehensive Income (Loss)


	Three Months Ended September 30, 2022						Three Months Ended September 30, 2021
(Thousands of dollars)	Before- Tax Amount		Tax (Expense) or Benefit (1)		Net-of- Tax Amount		Before- Tax Amount		Tax (Expense) or Benefit (1)		Net-of- Tax Amount
Defined benefit pension plans:
Amortization of prior service cost	$	44	$	(10)	$	34	$	239	$	(56)	$	183
Amortization of net actuarial (gain)/loss	8,705		(2,089)		6,616		11,151		(2,677)		8,474
Regulatory adjustment	(7,268)		1,744		(5,524)		(9,575)		2,298		(7,277)
Pension plans other comprehensive income (loss)	1,481		(355)		1,126		1,815		(435)		1,380
FSIRS (designated hedging activities):
Amounts reclassified into net income	—		—		—		544		(131)		413
FSIRS other comprehensive income (loss)	—		—		—		544		(131)		413
Total other comprehensive income (loss) - Southwest Gas Corporation	1,481		(355)		1,126		2,359		(566)		1,793
Foreign currency translation adjustments:
Translation adjustments	(5,830)		—		(5,830)		(2,056)		—		(2,056)
Foreign currency other comprehensive income (loss)	(5,830)		—		(5,830)		(2,056)		—		(2,056)
Total other comprehensive income (loss) - Southwest Gas Holdings, Inc.	$	(4,349)	$	(355)	$	(4,704)	$	303	$	(566)	$	(263)

	Nine Months Ended September 30, 2022						Nine Months Ended September 30, 2021
(Thousands of dollars)	Before- Tax Amount		Tax (Expense) or Benefit (1)		Net-of- Tax Amount		Before- Tax Amount		Tax (Expense) or Benefit (1)		Net-of- Tax Amount
Defined benefit pension plans:
Amortization of prior service cost	$	132	$	(32)	$	100	$	719	$	(172)	$	547
Amortization of net actuarial (gain)/loss	26,114		(6,267)		19,847		33,448		(8,028)		25,420
Regulatory adjustment	(21,804)		5,233		(16,571)		(28,725)		6,894		(21,831)
Pension plans other comprehensive income (loss)	4,442		(1,066)		3,376		5,442		(1,306)		4,136
FSIRS (designated hedging activities):
Amounts reclassified into net income	545		(129)		416		1,632		(392)		1,240
FSIRS other comprehensive income (loss)	545		(129)		416		1,632		(392)		1,240
Total other comprehensive income (loss) - Southwest Gas Corporation	4,987		(1,195)		3,792		7,074		(1,698)		5,376
Foreign currency translation adjustments:
Translation adjustments	(7,263)		—		(7,263)		(324)		—		(324)
Foreign currency other comprehensive income (loss)	(7,263)		—		(7,263)		(324)		—		(324)
Total other comprehensive income (loss) - Southwest Gas Holdings, Inc.	$	(2,276)	$	(1,195)	$	(3,471)	$	6,750	$	(1,698)	$	5,052


	Twelve Months Ended September 30, 2022						Twelve Months Ended September 30, 2021
(Thousands of dollars)	Before- Tax Amount		Tax (Expense) or Benefit (1)		Net-of- Tax Amount		Before- Tax Amount		Tax (Expense) or Benefit (1)		Net-of- Tax Amount
Defined benefit pension plans:
Net actuarial gain/(loss)	$	59,176	$	(14,202)	$	44,974	$	(57,539)	$	13,809	$	(43,730)
Amortization of prior service cost	372		(90)		282		1,007		(241)		766
Amortization of net actuarial (gain)/loss	37,263		(8,942)		28,321		42,906		(10,298)		32,608

Regulatory adjustment	(81,273)		19,506		(61,767)		3,894		(935)		2,959
Pension plans other comprehensive income (loss)	15,538		(3,728)		11,810		(9,732)		2,335		(7,397)
FSIRS (designated hedging activities):
Amounts reclassified into net income	1,087		(259)		828		2,176		(523)		1,653
FSIRS other comprehensive income (loss)	1,087		(259)		828		2,176		(523)		1,653
Total other comprehensive income (loss) - Southwest Gas Corporation	16,625		(3,987)		12,638		(7,556)		1,812		(5,744)
Foreign currency translation adjustments:
Translation adjustments	(6,919)		—		(6,919)		2,576		—		2,576
Foreign currency other comprehensive income (loss)	(6,919)		—		(6,919)		2,576		—		2,576
Total other comprehensive income (loss) - Southwest Gas Holdings, Inc.	$	9,706	$	(3,987)	$	5,719	$	(4,980)	$	1,812	$	(3,168)

Schedule of Rollforward of Accumulated Other Comprehensive Income

The following table represents a rollforward of AOCI, presented on the Company’s Condensed Consolidated Balance Sheets and its Condensed Consolidated Statements of Equity:


	Defined Benefit Plans						FSIRS						Foreign Currency Items
(Thousands of dollars)	Before-Tax		Tax (Expense) Benefit (4)		After-Tax		Before-Tax		Tax (Expense) Benefit (4)		After-Tax		Before-Tax		Tax (Expense) Benefit		After-Tax		AOCI
Beginning Balance AOCI December 31, 2021	$	(61,182)	$	14,685	$	(46,497)	$	(545)	$	129	$	(416)	$	152	$	—	$	152	$	(46,761)
Translation adjustments	—		—		—		—		—		—		(7,263)		—		(7,263)		(7,263)
Other comprehensive income (loss) before reclassifications	—		—		—		—		—		—		(7,263)		—		(7,263)		(7,263)
FSIRS amount reclassified from AOCI (1)	—		—		—		545		(129)		416		—		—		—		416
Amortization of prior service cost (2)	132		(32)		100		—		—		—		—		—		—		100
Amortization of net actuarial loss (2)	26,114		(6,267)		19,847		—		—		—		—		—		—		19,847
Regulatory adjustment (3)	(21,804)		5,233		(16,571)		—		—		—		—		—		—		(16,571)
Net current period other comprehensive income (loss) attributable to Southwest Gas Holdings, Inc.	4,442		(1,066)		3,376		545		(129)		416		(7,263)		—		(7,263)		(3,471)
Ending Balance AOCI September 30, 2022	$	(56,740)	$	13,619	$	(43,121)	$	—	$	—	$	—	$	(7,111)	$	—	$	(7,111)	$	(50,232)

(1)The FSIRS reclassification amount is included in Net interest deductions on the Company’s Condensed Consolidated Statements of Income.

(2)These AOCI components are included in the computation of net periodic benefit cost (see Note 2 – Components of Net Periodic Benefit Cost for additional details).

(4)Tax amounts are calculated using a 24% rate.

The following table represents a rollforward of AOCI, presented on Southwest’s Condensed Consolidated Balance Sheets:


	Defined Benefit Plans						FSIRS
(Thousands of dollars)	Before-Tax		Tax (Expense) Benefit (8)		After-Tax		Before-Tax		Tax (Expense) Benefit (8)		After-Tax		AOCI
Beginning Balance AOCI December 31, 2021	$	(61,182)	$	14,685	$	(46,497)	$	(545)	$	129	$	(416)	$	(46,913)
FSIRS amount reclassified from AOCI (5)	—		—		—		545		(129)		416		416
Amortization of prior service cost (6)	132		(32)		100		—		—		—		100
Amortization of net actuarial loss (6)	26,114		(6,267)		19,847		—		—		—		19,847
Regulatory adjustment (7)	(21,804)		5,233		(16,571)		—		—		—		(16,571)
Net current period other comprehensive income attributable to Southwest Gas Corporation	4,442		(1,066)		3,376		545		(129)		416		3,792
Ending Balance AOCI September 30, 2022	$	(56,740)	$	13,619	$	(43,121)	$	—	$	—	$	—	$	(43,121)

(5) The FSIRS reclassification amount is included in Net interest deductions on Southwest’s Condensed Consolidated Statements of Income.

(6)These AOCI components are included in the computation of net periodic benefit cost (see Note 2 – Components of Net Periodic Benefit Cost for additional details).

(8)Tax amounts are calculated using a 24% rate.

The following table represents amounts (before income tax impacts) included in AOCI (in the tables above), that have not yet been recognized in net periodic benefit cost:


(Thousands of dollars)	September 30, 2022		December 31, 2021
Net actuarial loss	$	(372,896)	$	(399,010)
Prior service cost	(1,396)		(1,528)
Less: amount recognized in regulatory assets	317,552		339,356
Recognized in AOCI	$	(56,740)	$	(61,182)

Schedule of Amount Recognized Before Income Tax in Accumulated Other Comprehensive Income

The following table represents amounts (before income tax impacts) included in AOCI (in the tables above), that have not yet been recognized in net periodic benefit cost:


(Thousands of dollars)	September 30, 2022		December 31, 2021
Net actuarial loss	$	(372,896)	$	(399,010)
Prior service cost	(1,396)		(1,528)
Less: amount recognized in regulatory assets	317,552		339,356
Recognized in AOCI	$	(56,740)	$	(61,182)

Segment Information (Tables)

9 Months Ended

Sep. 30, 2022

Segment Reporting [Abstract]

Schedule Of Accounts Receivable Not Eliminated During Consolidation

Accounts receivable for these services, which are not eliminated during consolidation, are presented in the table below:


(Thousands of dollars)	September 30, 2022		December 31, 2021
Centuri accounts receivable for services provided to Southwest	$	14,393	$	15,166

Schedule of Segment Reporting Information

The financial information pertaining to the natural gas distribution, utility infrastructure services, and pipeline and storage segments are as follows:


(Thousands of dollars)	Natural Gas Distribution		Utility Infrastructure Services		Pipeline and Storage		Other		Total
Three Months Ended September 30, 2022
Revenues from external customers	$	303,944	$	721,910	$	63,178	$	—	$	1,089,032
Intersegment revenues	—		36,556		—		—		36,556
Total	$	303,944	$	758,466	$	63,178	$	—	$	1,125,588
Segment net income (loss)	$	(22,199)	$	14,345	$	12,320	$	(16,775)	$	(12,309)

Three Months Ended September 30, 2021
Revenues from external customers	$	255,848	$	606,006	$	—	$	—	$	861,854
Intersegment revenues	—		26,842		—		—		26,842
Total	$	255,848	$	632,848	$	—	$	—	$	888,696
Segment net income (loss)	$	(27,544)	$	18,540	$	—	$	(2,572)	$	(11,576)

(Thousands of dollars)	Natural Gas Operations		Utility Infrastructure Services		Pipeline and Storage		Other		Total
Nine Months Ended September 30, 2022
Revenues from external customers	$	1,358,425	$	1,889,573	$	192,259	$	—	$	3,440,257
Intersegment revenues	—		98,860		—		—		98,860
Total	$	1,358,425	$	1,988,433	$	192,259	$	—	$	3,539,117
Segment net income (loss)	$	87,330	$	(4,400)	$	44,326	$	(49,962)	$	77,294

Nine Months Ended September 30, 2021
Revenues from external customers	$	1,070,576	$	1,450,719	$	—	$	—	$	2,521,295
Intersegment revenues	—		74,729		—		—		74,729
Total	$	1,070,576	$	1,525,448	$	—	$	—	$	2,596,024
Segment net income (loss)	$	102,584	$	32,797	$	—	$	(4,545)	$	130,836


(Thousands of dollars)	Natural Gas Distribution		Utility Infrastructure Services		Pipeline and Storage		Other		Total
Twelve Months Ended September 30, 2022
Revenues from external customers	$	1,809,639	$	2,495,169	$	192,259	$	—	$	4,497,067
Intersegment revenues	—		126,477		—		—		126,477
Total	$	1,809,639	$	2,621,646	$	192,259	$	—	$	4,623,544
Segment net income (loss)	$	171,881	$	3,223	$	44,326	$	(72,193)	$	147,237

Twelve Months Ended September 30, 2021
Revenues from external customers	$	1,445,066	$	1,957,667	$	—	$	—	$	3,402,733
Intersegment revenues	—		107,371		—		—		107,371
Total	$	1,445,066	$	2,065,038	$	—	$	—	$	3,510,104
Segment net income (loss)	$	182,134	$	56,723	$	—	$	(4,477)	$	234,380

Business Acquisitions (Tables)

9 Months Ended

Sep. 30, 2022

Business Combination and Asset Acquisition [Abstract]

Summary of Fair Values of Assets Acquired and Liabilities Assumed

The final estimated fair values of assets acquired and liabilities assumed as of August 27, 2021, and as updated through August 27, 2022, are as follows:


(Millions of dollars)	Acquisition Date		Measurement Period Adjustments		Revised Acquisition Date
Cash and cash equivalents	$	1.9	$	—	$	1.9
Accounts receivable	69.1		(8.6)		60.5
Contract assets	40.1		7.4		47.5
Income taxes receivable, net	0.7		(0.3)		0.4
Right of use assets under operating leases	1.5		—		1.5
Prepaid expenses	5.2		—		5.2
Property and equipment	118.1		1.2		119.3
Intangible assets	335.0		(31.5)		303.5
Goodwill	446.8		0.8		447.6
Total assets acquired	1,018.4		(31.0)		987.4

Trade and other payables	46.2		—		46.2
Finance lease obligations	27.5		1.2		28.7
Contract liabilities	12.7		0.1		12.8
Operating lease obligations	1.5		—		1.5
Other liabilities	5.3		(1.2)		4.1
Deferred tax liabilities	94.8		(24.8)		70.0
Total liabilities assumed and noncontrolling interest	188.0		(24.7)		163.3
Net assets acquired	$	830.4	$	(6.3)	$	824.1

The estimated fair values of assets acquired and liabilities assumed as of December 31, 2021, as updated through September 30, 2022, are as follows:


(Millions of dollars)	Acquisition Date		Measurement Period Adjustments		Revised Acquisition Date
Gas plant, net	$	1,047.4	$	—	$	1,047.4
Other property and investments	51.3		—		51.3
Cash and cash equivalents	17.6		—		17.6
Accounts receivable, net of allowances	26.6		2.9		29.5
Prepaid and other current assets	27.4		—		27.4
Deferred charges and other assets	31.1		—		31.1
Goodwill	986.2		(28.2)		958.0
Deferred income taxes, net	15.4		20.9		36.3
Total assets acquired	2,203.0		(4.4)		2,198.6

Long-term debt	449.7		—		449.7
Accounts payable	7.0		—		7.0
Deferred purchased gas costs	5.7		—		5.7
Customer deposits	3.2		—		3.2
Accrued general taxes	0.4		—		0.4
Accrued interest	4.7		—		4.7
Other current liabilities	14.5		—		14.5
Accumulated removal costs	56.6		—		56.6
Other deferred credits	85.6		—		85.6
Total liabilities assumed	627.4		—		627.4
Net assets acquired	$	1,575.6	$	(4.4)	$	1,571.2

Background, Organization, and Summary of Significant Accounting Policies - Narratives (Details)	1 Months Ended		3 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2022 USD ($)	Aug. 31, 2021 person	Jun. 30, 2022 USD ($)	Sep. 30, 2022 USD ($) director	Sep. 30, 2022 USD ($) director	May 09, 2022	Dec. 31, 2021 USD ($)	Nov. 30, 2021	Oct. 10, 2021	Nov. 30, 2018
Significant Accounting Policies [Line Items]
Rights agreement amendment, beneficial ownership percentage						24.90%			10.00%
Capital expenditures incurred but not yet paid, increase (decrease)				$ (4,800,000)	$ 16,100,000
Deferred purchased gas costs recovered or refunded period				1 year
Gas pipe materials and operating supplies				$ 80,800,000	80,800,000		$ 67,400,000
Accrued purchased gas cost				15,500,000	15,500,000		51,600,000
Goodwill impairment				0
Dividends declared but not yet paid				41,600,000	41,600,000		36,000,000
Payments for redemption of redeemable noncontrolling interest	$ 39,600,000
Percentage of redeemable noncontrolling interest redeemed	5.00%
Redemption value adjustments				44,933,000
Loss contingency, number of individuals injured \| person		4
Linetec
Significant Accounting Policies [Line Items]
Redemption value adjustments				44,933,000
Drum
Significant Accounting Policies [Line Items]
Redemption value adjustments				0
Money Market Funds
Significant Accounting Policies [Line Items]
Money market fund investments				56,000,000	56,000,000		20,000,000
Southwest Gas Corporation
Significant Accounting Policies [Line Items]
Capital expenditures incurred but not yet paid, increase (decrease)				(11,600,000)	9,400,000
Gas pipe materials and operating supplies				76,500,000	76,500,000		62,900,000
Accrued purchased gas cost				15,500,000	15,500,000		51,600,000
Self-insured retention amount				1,000,000	1,000,000
Threshold amount above self-insured retention				4,000,000	4,000,000
Loss contingency, maximum				5,000,000	5,000,000
Loss contingency accrual							5,000,000
Loss contingency recorded			$ 6,200,000
Southwest Gas Corporation \| Money Market Funds
Significant Accounting Policies [Line Items]
Money market fund investments				$ 0	$ 0		$ 0
Previous Owner Of Linetec \| Linetec
Significant Accounting Policies [Line Items]
Ownership percentage by noncontrolling owners	15.00%									20.00%
Certain Members Of Riggs Distler Management \| Drum
Significant Accounting Policies [Line Items]
Ownership percentage by noncontrolling owners				1.42%	1.42%			1.42%
Minimum
Significant Accounting Policies [Line Items]
Number of new board of directors appointed \| director				2	2
Minimum \| Centuri
Significant Accounting Policies [Line Items]
Entity separation, completion period	9 months
Maximum \| Centuri
Significant Accounting Policies [Line Items]
Entity separation, completion period	12 months

Background, Organization, and Summary of Significant Accounting Policies - Schedule of Other Property and Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Other property and investments	$ 56,812	$ 59,337
Total	1,311,334	1,316,479
Non-regulated property, equipment, and intangibles	1,704,354	1,616,392
Non-regulated accumulated provision for depreciation and amortization	(595,393)	(512,343)
Southwest Gas Corporation
Property, Plant and Equipment [Line Items]
Net cash surrender value of COLI policies	141,705	149,947
Other property and investments	3,856	3,146
Total	$ 145,561	$ 153,093

Background, Organization, and Summary of Significant Accounting Policies - Schedule of Goodwill (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2022 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 1,781,332
Foreign currency translation adjustment	(8,264)
Goodwill, ending balance	1,742,967
Riggs Distler
Goodwill [Roll Forward]
Measurement period adjustments	(1,924)
MountainWest
Goodwill [Roll Forward]
Measurement period adjustments	(28,177)
Natural Gas Distribution
Goodwill [Roll Forward]
Goodwill, beginning balance	10,095
Foreign currency translation adjustment	0
Goodwill, ending balance	10,095
Natural Gas Distribution \| Riggs Distler
Goodwill [Roll Forward]
Measurement period adjustments	0
Natural Gas Distribution \| MountainWest
Goodwill [Roll Forward]
Measurement period adjustments	0
Utility Infrastructure Services
Goodwill [Roll Forward]
Goodwill, beginning balance	785,058
Foreign currency translation adjustment	(8,264)
Goodwill, ending balance	774,870
Utility Infrastructure Services \| Riggs Distler
Goodwill [Roll Forward]
Measurement period adjustments	(1,924)
Utility Infrastructure Services \| MountainWest
Goodwill [Roll Forward]
Measurement period adjustments	0
Pipeline and Storage
Goodwill [Roll Forward]
Goodwill, beginning balance	986,179
Foreign currency translation adjustment	0
Goodwill, ending balance	958,002
Pipeline and Storage \| Riggs Distler
Goodwill [Roll Forward]
Measurement period adjustments	0
Pipeline and Storage \| MountainWest
Goodwill [Roll Forward]
Measurement period adjustments	$ (28,177)

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References + Details

Background, Organization, and Summary of Significant Accounting Policies - Other Income (Deductions) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Other income (deductions)
Equity AFUDC	$ 246	$ 0	$ 664	$ 0	$ 664	$ 0
Miscellaneous income and (expense)	(773)	1,115	(2,124)	778	(2,046)	687
Foreign transaction gain (loss)	(182)	(7)	35	(19)	32	(19)
Equity in earnings of unconsolidated investments	624	67	1,867	168	1,925	159
Total other income (deductions)	1,593	(3,112)	2	(3,975)	478	282
Southwest Gas Corporation
Other income (deductions)
Change in COLI policies	(1,500)	0	(8,700)	5,800	(5,700)	14,000
Interest income	4,356	1,365	10,355	3,312	12,156	4,113
Equity AFUDC	91	0	248	0	248	1,311
Other components of net periodic benefit cost	(188)	(3,506)	(563)	(10,516)	(4,068)	(15,522)
Miscellaneous income and (expense)	(1,081)	(2,146)	(1,780)	(3,498)	(2,733)	(4,447)
Total other income (deductions)	$ 1,678	$ (4,287)	$ (440)	$ (4,902)	$ (97)	$ (545)

Background, Organization, and Summary of Significant Accounting Policies - Summary of Redeemable Noncontrolling Interest (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2022 USD ($)
Movement In Redeemable Noncontrolling Interest [Roll Forward]
Redeemable noncontrolling interest, beginning balance	$ 196,717
Net income (loss) attributable to redeemable noncontrolling interests	2,557
Redemption value adjustments	(44,933)
Redemption of equity interest from noncontrolling party	(39,649)
Redeemable noncontrolling interest, ending balance	114,692
Linetec
Movement In Redeemable Noncontrolling Interest [Roll Forward]
Redeemable noncontrolling interest, beginning balance	184,148
Net income (loss) attributable to redeemable noncontrolling interests	2,582
Redemption value adjustments	(44,933)
Redemption of equity interest from noncontrolling party	(39,649)
Redeemable noncontrolling interest, ending balance	102,148
Drum
Movement In Redeemable Noncontrolling Interest [Roll Forward]
Redeemable noncontrolling interest, beginning balance	12,569
Net income (loss) attributable to redeemable noncontrolling interests	(25)
Redemption value adjustments	0
Redemption of equity interest from noncontrolling party	0
Redeemable noncontrolling interest, ending balance	$ 12,544

Background, Organization, and Summary of Significant Accounting Policies - Schedule of Earnings Per Share (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Weighted average basic shares (in shares)	67,157	59,688	65,004	58,639	63,905	58,209
Effect of dilutive securities:
Restricted stock units (in shares)	168	128	144	103	146	103
Weighted average diluted shares (in shares)	67,325	59,816	65,148	58,742	64,051	58,312
Number of performance share units granted (in shares)	156	115	135	95	135	93

Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Qualified Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 11,028	$ 10,289	$ 33,084	$ 30,869	$ 43,374	$ 39,443
Interest cost	11,251	10,108	33,753	30,324	43,861	41,714
Expected return on plan assets	(19,978)	(18,088)	(59,934)	(54,264)	(78,022)	(70,588)
Amortization of net actuarial loss	8,117	10,489	24,351	31,467	34,839	40,473
Net periodic benefit cost	10,418	12,798	31,254	38,396	44,052	51,042
SERP
Defined Benefit Plan Disclosure [Line Items]
Service cost	106	131	318	394	450	491
Interest cost	360	358	1,080	1,074	1,437	1,474
Amortization of net actuarial loss	588	661	1,763	1,981	2,424	2,433
Net periodic benefit cost	1,054	1,150	3,161	3,449	4,311	4,398
PBOP
Defined Benefit Plan Disclosure [Line Items]
Service cost	485	423	1,455	1,269	1,877	1,664
Interest cost	613	549	1,839	1,645	2,387	2,291
Expected return on plan assets	(807)	(810)	(2,421)	(2,430)	(3,230)	(3,282)
Amortization of prior service costs	44	239	132	719	372	1,007
Net periodic benefit cost	$ 335	$ 401	$ 1,005	$ 1,203	$ 1,406	$ 1,680

Revenue - Schedule of Regulated Operations Revenues: Natural Gas Distribution Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Disaggregation of Revenue [Line Items]
Total Regulated operations revenues	$ 367,122	$ 255,848	$ 1,550,684	$ 1,070,576	$ 2,001,898	$ 1,445,066
Natural Gas Distribution
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	287,821	241,300	1,346,687	1,068,164	1,776,273	1,440,374
Alternative revenue program revenues (deferrals)	13,609	12,569	1,132	(5,335)	19,648	(2,740)
Other revenues	2,514	1,979	10,606	7,747	13,718	7,432
Total Regulated operations revenues	303,944	255,848	1,358,425	1,070,576	1,809,639	1,445,066
Residential \| Natural Gas Distribution
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	170,196	147,326	913,355	743,791	1,205,176	1,011,450
Small commercial \| Natural Gas Distribution
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	61,780	48,283	264,494	185,774	348,934	248,193
Large commercial \| Natural Gas Distribution
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	19,590	14,199	60,740	40,030	78,081	52,075
Industrial/other \| Natural Gas Distribution
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	13,319	9,608	34,064	30,352	46,025	37,505
Transportation \| Natural Gas Distribution
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 22,936	$ 21,884	$ 74,034	$ 68,217	$ 98,057	$ 91,151

Revenue - Schedule of Regulated Operations Revenues: Utility Infrastructure Services Segment (Details) - Centuri - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 758,466	$ 632,848	$ 1,988,433	$ 1,525,448	$ 2,621,646	$ 2,065,038
Master services agreement
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	637,582	467,869	1,700,416	1,160,199	2,193,195	1,573,247
Bid contract
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	120,884	164,979	288,017	365,249	428,451	491,791
Unit price contracts
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	453,718	406,404	1,178,168	1,002,779	1,544,471	1,373,746
Fixed price contracts
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	117,983	64,632	333,313	149,681	451,374	197,447
Time and materials contracts
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	186,765	161,812	476,952	372,988	625,801	493,845
Gas infrastructure services
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	467,751	393,122	1,147,302	961,836	1,487,806	1,287,552
Electric power infrastructure services
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	189,209	155,456	550,926	347,061	729,067	475,895
Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 101,506	$ 84,270	$ 290,205	$ 216,551	$ 404,773	$ 301,591

Revenue - Summary of Information about Receivables (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Revenue from Contract with Customer [Abstract]
Contracts receivable, net	$ 398,345	$ 296,005
Revenue earned on contracts in progress in excess of billings	253,966	214,774
Amounts billed in excess of revenue earned on contracts	$ 31,877	$ 11,860

Revenue - Narratives (Details) $ in Millions	9 Months Ended
Revenue - Narratives (Details) $ in Millions	Sep. 30, 2022 USD ($) contract
Segment Reporting Information [Line Items]
Change in contract liability, revenue recognized	$ 11.9
Centuri
Segment Reporting Information [Line Items]
Number of contracts with original duration more than one year \| contract	61
Centuri \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-10-01
Segment Reporting Information [Line Items]
Transaction price allocated to unsatisfied performance obligations of contracts	$ 430.3
Transaction price allocated to unsatisfied performance obligations of contracts, period	2 years 8 months 12 days

Revenue - Schedule of Utility Infrastructure Services Contracts Receivable (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Contracts receivable, net	$ 398,345	$ 296,005
Utility Infrastructure Services
Disaggregation of Revenue [Line Items]
Contracts receivable, gross	402,716	296,262
Allowance for doubtful accounts	(4,371)	(257)
Contracts receivable, net	398,345	296,005
Utility Infrastructure Services \| Billed on completed contracts and contracts in progress
Disaggregation of Revenue [Line Items]
Contracts receivable, gross	400,831	292,770
Utility Infrastructure Services \| Other receivables
Disaggregation of Revenue [Line Items]
Contracts receivable, gross	$ 1,885	$ 3,492

Revenue - Schedule of Regulated Operations Revenues: Pipeline and Storage Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Segment Reporting Information [Line Items]
Total Regulated operations revenues	$ 367,122	$ 255,848	$ 1,550,684	$ 1,070,576	$ 2,001,898	$ 1,445,066
Pipeline and Storage
Segment Reporting Information [Line Items]
Revenue from contracts with customers	63,137		192,128
Other revenues	41		131
Total Regulated operations revenues	63,178		192,259
Pipeline and Storage \| Regulated gas transportation and storage revenues
Segment Reporting Information [Line Items]
Revenue from contracts with customers	59,283		179,046
Pipeline and Storage \| NGL revenues
Segment Reporting Information [Line Items]
Revenue from contracts with customers	1,469		4,838
Pipeline and Storage \| Other revenues
Segment Reporting Information [Line Items]
Revenue from contracts with customers	$ 2,385		$ 8,244

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8906-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 40
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e9031-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e9038-108599

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130543-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e9054-108599

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130545-203045

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 924
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-URI https://asc.fasb.org/extlink&oid=6472922&loc=d3e499488-122856

+ Details

Common Stock - Narratives (Details) - USD ($) $ / shares in Units, shares in Thousands	1 Months Ended		9 Months Ended
	Mar. 31, 2022	Nov. 30, 2021	Sep. 30, 2022	May 09, 2022	Oct. 10, 2021	Apr. 08, 2021
Class of Stock [Line Items]
Sale of stock, number of shares	6,325
Sale of stock, price per share (in USD per share)			$ 74.00
Net proceeds from sale of stock	$ 452,300,000
Sale of stock, underwriters' discount	$ 15,800,000
Rights agreement amendment, beneficial ownership percentage				24.90%	10.00%
Term Loan Facility Due December 30, 2022 \| Loans Payable
Class of Stock [Line Items]
Debt instrument, term		364 days
Restricted Stock/Unit Plan, and Management Incentive Plan
Class of Stock [Line Items]
Common stock issued (in shares)			216
Dividend Reinvestment and Stock Purchase Plan
Class of Stock [Line Items]
Common stock issued (in shares)			100
Common stock issued, amount			$ 7,800,000
Equity Shelf Program
Class of Stock [Line Items]
Sale of stock, amount of common stock offered for sale						$ 500,000,000
Sale of stock, amount of common stock available for sale			$ 341,800,000

Common Stock - Activity of Equity Shelf Program (Details) - USD ($)	9 Months Ended		12 Months Ended		18 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022
Class of Stock [Line Items]
Net proceeds	$ 459,051,000	$ 210,812,000	$ 461,880,000	$ 259,422,000
Equity Shelf Program
Class of Stock [Line Items]
Gross proceeds					$ 158,180,343
Less: agent commissions					(1,581,803)
Net proceeds					$ 156,598,540
Number of shares sold (in shares)					2,302,407
Weighted average price per share (in USD per share)					$ 68.70

Debt - Schedule of Carrying Amounts and Estimated Fair Values of Long-Term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 26, 2022	Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Less: current maturities	$ (41,485)			$ (297,324)
Long-term debt, less current maturities	5,865,591			4,115,684
Southwest Gas Corporation
Debt Instrument [Line Items]
Less: current maturities	0			(275,000)
Long-term debt, less current maturities	$ 3,042,082			$ 2,440,603
MountainWest unsecured senior notes, 3.53%, due in 2028
Debt Instrument [Line Items]
Debt instrument interest rate	3.53%
MountainWest unsecured senior notes, 4.875%, due in 2041
Debt Instrument [Line Items]
Debt instrument interest rate	4.875%
MountainWest unsecured senior notes, 3.91%, due in 2038
Debt Instrument [Line Items]
Debt instrument interest rate	3.91%
Debentures \| Notes, 6.1%, due 2041 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Debt instrument interest rate	6.10%
Debentures \| Notes, 4.05%, due 2032 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Debt instrument interest rate	4.05%		4.05%
Debentures \| Notes, 3.875%, due 2022 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Debt instrument interest rate				3.875%
Debentures \| Notes, 4.875%, due 2043 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Debt instrument interest rate	4.875%
Debentures \| Notes, 3.8%, due 2046 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Debt instrument interest rate	3.80%
Debentures \| Notes, 3.7%, due 2028 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Debt instrument interest rate	3.70%
Debentures \| Notes, 4.15%, due 2049 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Debt instrument interest rate	4.15%
Debentures \| Notes, 2.2%, due 2030 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Debt instrument interest rate	2.20%
Debentures \| Notes, 3.18%, due 2051 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Debt instrument interest rate	3.18%
Debentures \| 8% Series, due 2026 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Debt instrument interest rate	8.00%
Debentures \| Medium-term notes, 7.78% series, due 2022 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Debt instrument interest rate				7.78%
Debentures \| Medium-term notes, 7.92% series, due 2027 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Debt instrument interest rate	7.92%
Debentures \| Medium-term notes, 6.76% series, due 2027 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Debt instrument interest rate	6.76%
Loans Payable \| SWH Term Loan Facility
Debt Instrument [Line Items]
Long-term debt, gross		$ 1,150,000
Secured Debt \| Centuri Secured Term Loan Facility \| Centuri
Debt Instrument [Line Items]
Long-term debt, gross	$ 1,009,000
Carrying Amount
Debt Instrument [Line Items]
Unamortized discount and debt issuance costs	(25,234)			$ (24,466)
Less: current maturities	(41,485)			(22,324)
Long-term debt, less current maturities	5,865,591			4,115,684
Carrying Amount \| Southwest Gas Corporation
Debt Instrument [Line Items]
Less: current maturities	0			(275,000)
Long-term debt, less current maturities	3,042,082			2,440,603
Carrying Amount \| Centuri \| Centuri secured revolving credit facility
Debt Instrument [Line Items]
Long-term debt, gross	150,571			103,329
Carrying Amount \| Debentures \| Southwest Gas Corporation
Debt Instrument [Line Items]
Unamortized discount and debt issuance costs	(26,701)			(19,959)
Long-term debt	2,705,799			2,387,541
Carrying Amount \| Debentures \| Notes, 6.1%, due 2041 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	125,000			125,000
Carrying Amount \| Debentures \| Notes, 4.05%, due 2032 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	600,000			0
Carrying Amount \| Debentures \| Notes, 3.875%, due 2022 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	0			250,000
Carrying Amount \| Debentures \| Notes, 4.875%, due 2043 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	250,000			250,000
Carrying Amount \| Debentures \| Notes, 3.8%, due 2046 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	300,000			300,000
Carrying Amount \| Debentures \| Notes, 3.7%, due 2028 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	300,000			300,000
Carrying Amount \| Debentures \| Notes, 4.15%, due 2049 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	300,000			300,000
Carrying Amount \| Debentures \| Notes, 2.2%, due 2030 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	450,000			450,000
Carrying Amount \| Debentures \| Notes, 3.18%, due 2051 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	300,000			300,000
Carrying Amount \| Debentures \| 8% Series, due 2026 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	75,000			75,000
Carrying Amount \| Debentures \| Medium-term notes, 7.78% series, due 2022 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	0			25,000
Carrying Amount \| Debentures \| Medium-term notes, 7.92% series, due 2027 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	25,000			25,000
Carrying Amount \| Debentures \| Medium-term notes, 6.76% series, due 2027 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	7,500			7,500
Carrying Amount \| Revolving credit facility and commercial paper \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt	138,000			130,000
Carrying Amount \| Industrial development revenue bonds \| Southwest Gas Corporation
Debt Instrument [Line Items]
Unamortized discount and debt issuance costs	(1,717)			(1,938)
Long-term debt	198,283			198,062
Carrying Amount \| Industrial development revenue bonds \| Tax-exempt Series A, due 2028 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	50,000			50,000
Carrying Amount \| Industrial development revenue bonds \| 2003 Series A, due 2038 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	50,000			50,000
Carrying Amount \| Industrial development revenue bonds \| 2008 Series A, due 2038 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	50,000			50,000
Carrying Amount \| Industrial development revenue bonds \| 2009 Series A, due 2039 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	50,000			50,000
Carrying Amount \| Loans Payable \| SWH Term Loan Facility
Debt Instrument [Line Items]
Long-term debt, gross	1,147,747			0
Carrying Amount \| Secured Debt \| Centuri Secured Term Loan Facility \| Centuri
Debt Instrument [Line Items]
Long-term debt, gross	1,008,550			1,117,138
Carrying Amount \| Unsecured Debt \| MountainWest unsecured senior notes, 3.53%, due in 2028
Debt Instrument [Line Items]
Long-term debt, gross	101,843			102,078
Carrying Amount \| Unsecured Debt \| MountainWest unsecured senior notes, 4.875%, due in 2041
Debt Instrument [Line Items]
Long-term debt, gross	199,431			199,926
Carrying Amount \| Unsecured Debt \| MountainWest unsecured senior notes, 3.91%, due in 2038
Debt Instrument [Line Items]
Long-term debt, gross	147,812			147,735
Carrying Amount \| Other debt obligations
Debt Instrument [Line Items]
Long-term debt, gross	134,274			51,665
Fair Value \| Centuri \| Centuri secured revolving credit facility
Debt Instrument [Line Items]
Long-term debt, gross	150,740			103,749
Fair Value \| Debentures \| Notes, 6.1%, due 2041 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	113,398			166,380
Fair Value \| Debentures \| Notes, 4.05%, due 2032 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	506,346			0
Fair Value \| Debentures \| Notes, 3.875%, due 2022 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	0			250,603
Fair Value \| Debentures \| Notes, 4.875%, due 2043 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	202,383			307,538
Fair Value \| Debentures \| Notes, 3.8%, due 2046 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	203,559			329,055
Fair Value \| Debentures \| Notes, 3.7%, due 2028 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	267,903			325,191
Fair Value \| Debentures \| Notes, 4.15%, due 2049 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	213,972			342,030
Fair Value \| Debentures \| Notes, 2.2%, due 2030 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	340,763			440,838
Fair Value \| Debentures \| Notes, 3.18%, due 2051 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	182,976			292,116
Fair Value \| Debentures \| 8% Series, due 2026 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	80,108			92,623
Fair Value \| Debentures \| Medium-term notes, 7.78% series, due 2022 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	0			25,122
Fair Value \| Debentures \| Medium-term notes, 7.92% series, due 2027 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	26,413			31,555
Fair Value \| Debentures \| Medium-term notes, 6.76% series, due 2027 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	7,494			8,949
Fair Value \| Revolving credit facility and commercial paper \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt	138,000			130,000
Fair Value \| Industrial development revenue bonds \| Tax-exempt Series A, due 2028 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	50,000			50,000
Fair Value \| Industrial development revenue bonds \| 2003 Series A, due 2038 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	50,000			50,000
Fair Value \| Industrial development revenue bonds \| 2008 Series A, due 2038 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	50,000			50,000
Fair Value \| Industrial development revenue bonds \| 2009 Series A, due 2039 \| Southwest Gas Corporation
Debt Instrument [Line Items]
Long-term debt, gross	50,000			50,000
Fair Value \| Loans Payable \| SWH Term Loan Facility
Debt Instrument [Line Items]
Long-term debt, gross	1,148,057			0
Fair Value \| Secured Debt \| Centuri Secured Term Loan Facility \| Centuri
Debt Instrument [Line Items]
Long-term debt, gross	977,033			1,117,841
Fair Value \| Unsecured Debt \| MountainWest unsecured senior notes, 3.53%, due in 2028
Debt Instrument [Line Items]
Long-term debt, gross	86,345			102,078
Fair Value \| Unsecured Debt \| MountainWest unsecured senior notes, 4.875%, due in 2041
Debt Instrument [Line Items]
Long-term debt, gross	152,581			199,926
Fair Value \| Unsecured Debt \| MountainWest unsecured senior notes, 3.91%, due in 2038
Debt Instrument [Line Items]
Long-term debt, gross	103,398			147,735
Fair Value \| Other debt obligations
Debt Instrument [Line Items]
Long-term debt, gross	$ 122,980			$ 50,003

Debt - Narratives (Details)	1 Months Ended	9 Months Ended
Debt - Narratives (Details)	Nov. 30, 2021 USD ($)	Sep. 30, 2022 USD ($) instrument	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 26, 2022 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Debt Instrument [Line Items]
Current maturities of long-term debt		$ 41,485,000						$ 297,324,000
Short-term debt		381,000,000						1,909,000,000
Carrying Amount
Debt Instrument [Line Items]
Current maturities of long-term debt		41,485,000						22,324,000
SWH Term Loan Facility \| Loans Payable
Debt Instrument [Line Items]
Long-term debt, gross						$ 1,150,000,000
Debt nonrefundable upfront fees, percentage of outstanding principal balance						0.10%
SWH Term Loan Facility \| Loans Payable \| Forecast
Debt Instrument [Line Items]
Debt nonrefundable upfront fees, percentage of outstanding principal balance			0.20%	0.15%	0.10%
SWH Term Loan Facility \| Loans Payable \| Carrying Amount
Debt Instrument [Line Items]
Long-term debt, gross		1,147,747,000						0
Term Loan Facility Due December 30, 2022 \| Loans Payable
Debt Instrument [Line Items]
Debt instrument face amount	$ 1,600,000,000
Debt instrument, term	364 days
Southwest Gas Corporation
Debt Instrument [Line Items]
Current maturities of long-term debt		0						275,000,000
Short-term debt		225,000,000						250,000,000
Southwest Gas Corporation \| Carrying Amount
Debt Instrument [Line Items]
Current maturities of long-term debt		0						275,000,000
Southwest Gas Corporation \| Debentures \| Carrying Amount
Debt Instrument [Line Items]
Long-term debt outstanding		$ 2,705,799,000						2,387,541,000
Southwest Gas Corporation \| Notes, 4.05%, due 2032 \| Debentures
Debt Instrument [Line Items]
Debt instrument face amount							$ 600,000,000
Debt instrument interest rate		4.05%					4.05%
Debt instrument discount rate							0.65%
Southwest Gas Corporation \| Notes, 4.05%, due 2032 \| Debentures \| Carrying Amount
Debt Instrument [Line Items]
Long-term debt, gross		$ 600,000,000						$ 0
Southwest Gas Corporation \| Notes, 3.875%, due 2022 \| Debentures
Debt Instrument [Line Items]
Debt instrument face amount							$ 250,000,000
Debt instrument interest rate								3.875%
Southwest Gas Corporation \| Notes, 3.875%, due 2022 \| Debentures \| Carrying Amount
Debt Instrument [Line Items]
Long-term debt, gross		0						$ 250,000,000
Southwest Gas Corporation \| March 2021 Term Loan
Debt Instrument [Line Items]
Debt instrument face amount							$ 250,000,000
Short-term debt		225,000,000
Centuri \| Centuri Secured Term Loan Facility And Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		1,545,000,000
Borrowings outstanding under facility		1,159,000,000
Debt secured by assets		2,600,000,000
Centuri \| Centuri secured term loan facility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		1,145,000,000
Centuri \| Centuri Secured Term Loan Facility \| Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross		1,009,000,000.000
Centuri \| Centuri Secured Term Loan Facility \| Secured Debt \| Carrying Amount
Debt Instrument [Line Items]
Long-term debt, gross		$ 1,008,550,000						1,117,138,000
MountainWest
Debt Instrument [Line Items]
Number of private placement \| instrument		2
MountainWest \| Unsecured Debt
Debt Instrument [Line Items]
Debt instrument face amount		$ 430,000,000
Long-term debt, gross		449,100,000
$400 Million Credit Facility \| Southwest Gas Corporation
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		400,000,000
Line of credit designated as long term debt		150,000,000
Line of credit designated for working capital purposes		250,000,000
Long-term debt outstanding		138,000,000
Current maturities of long-term debt		0
Short-term debt		$ 0
$400 Million Credit Facility \| Southwest Gas Corporation \| SOFR
Debt Instrument [Line Items]
Debt, basis spread on variable rate		1.125%
$400 Million Credit Facility \| Southwest Gas Corporation \| Alternative base rate
Debt Instrument [Line Items]
Debt, basis spread on variable rate		0.125%
Commercial Paper Program \| Southwest Gas Corporation
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		$ 50,000,000
Borrowings outstanding under facility		0
Centuri secured revolving credit facility \| Centuri \| Carrying Amount
Debt Instrument [Line Items]
Long-term debt, gross		150,571,000						$ 103,329,000
Centuri secured revolving credit facility \| Centuri \| Line of Credit
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		400,000,000
$100 Million Credit Facility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		200,000,000
Borrowings outstanding under facility		$ 156,000,000

Other Comprehensive Income and Accumulated Other Comprehensive Income - Related Tax Effects Allocated to OCI (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), before tax	$ (4,349)	$ 303	$ (2,276)	$ 6,750	$ 9,706	$ (4,980)
Other comprehensive income (loss), tax	(355)	(566)	(1,195)	(1,698)	(3,987)	1,812
Total other comprehensive income (loss), net of tax	(4,704)	(263)	(3,471)	$ 5,052	5,719	(3,168)
Other comprehensive income (loss) before reclassifications, net of tax			$ (7,263)
Effective income tax rate			24.00%	24.00%
Southwest Gas Corporation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), before tax	1,481	2,359	$ 4,987	$ 7,074	16,625	(7,556)
Other comprehensive income (loss), tax	(355)	(566)	(1,195)	(1,698)	(3,987)	1,812
Total other comprehensive income (loss), net of tax	1,126	1,793	3,792	5,376	12,638	(5,744)
Pension plans other comprehensive income (loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), before tax	1,481	1,815	4,442	5,442	15,538	(9,732)
Other comprehensive income (loss), tax	(355)	(435)	(1,066)	(1,306)	(3,728)	2,335
Total other comprehensive income (loss), net of tax	1,126	1,380	3,376	4,136	11,810	(7,397)
Pension plans other comprehensive income (loss) \| Southwest Gas Corporation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), before tax			4,442
Other comprehensive income (loss), tax			(1,066)
Total other comprehensive income (loss), net of tax			3,376
Amortization of prior service cost
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from AOCI, before Tax	44	239	132	719	372	1,007
Reclassification from AOCI, tax	(10)	(56)	(32)	(172)	(90)	(241)
Reclassification from AOCI, net of tax	34	183	100	547	282	766
Other comprehensive income (loss), before tax			132
Other comprehensive income (loss), tax			(32)
Total other comprehensive income (loss), net of tax			100
Amortization of prior service cost \| Southwest Gas Corporation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), before tax			132
Other comprehensive income (loss), tax			(32)
Total other comprehensive income (loss), net of tax			100
Amortization of net actuarial (gain)/loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from AOCI, before Tax	8,705	11,151	26,114	33,448	37,263	42,906
Reclassification from AOCI, tax	(2,089)	(2,677)	(6,267)	(8,028)	(8,942)	(10,298)
Reclassification from AOCI, net of tax	6,616	8,474	19,847	25,420	28,321	32,608
Other comprehensive income (loss), before tax			26,114
Other comprehensive income (loss), tax			(6,267)
Total other comprehensive income (loss), net of tax			19,847
Other comprehensive income (loss) before reclassifications, before tax					59,176	(57,539)
Other comprehensive income (loss) before reclassifications, tax					(14,202)	13,809
Other comprehensive income (loss) before reclassifications, net of tax					44,974	(43,730)
Amortization of net actuarial (gain)/loss \| Southwest Gas Corporation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), before tax			26,114
Other comprehensive income (loss), tax			(6,267)
Total other comprehensive income (loss), net of tax			19,847
Regulatory adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from AOCI, before Tax	(7,268)	(9,575)	(21,804)	(28,725)	(81,273)	3,894
Reclassification from AOCI, tax	1,744	2,298	5,233	6,894	19,506	(935)
Reclassification from AOCI, net of tax	(5,524)	(7,277)	(16,571)	(21,831)	(61,767)	2,959
Other comprehensive income (loss), before tax			(21,804)
Other comprehensive income (loss), tax			5,233
Total other comprehensive income (loss), net of tax			(16,571)
Regulatory adjustment \| Southwest Gas Corporation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), before tax			(21,804)
Other comprehensive income (loss), tax			5,233
Total other comprehensive income (loss), net of tax			(16,571)
FSIRS
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from AOCI, before Tax	0	544	545	1,632	1,087	2,176
Reclassification from AOCI, tax	0	(131)	(129)	(392)	(259)	(523)
Reclassification from AOCI, net of tax	0	413	416	1,240	828	1,653
Other comprehensive income (loss), before tax	0	544	545	1,632	1,087	2,176
Other comprehensive income (loss), tax	0	(131)	(129)	(392)	(259)	(523)
Total other comprehensive income (loss), net of tax	0	413	416	1,240	828	1,653
FSIRS \| Southwest Gas Corporation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from AOCI, before Tax			545
Reclassification from AOCI, tax			(129)
Reclassification from AOCI, net of tax			416
Other comprehensive income (loss), before tax			545
Other comprehensive income (loss), tax			(129)
Total other comprehensive income (loss), net of tax			416
Foreign currency items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, before tax	(5,830)	(2,056)	(7,263)	(324)	(6,919)	2,576
Other comprehensive income (loss) before reclassifications, tax	0	0	0	0	0	0
Other comprehensive income (loss) before reclassifications, net of tax	$ (5,830)	$ (2,056)	$ (7,263)	$ (324)	$ (6,919)	$ 2,576

Other Comprehensive Income and Accumulated Other Comprehensive Income - AOCI Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance, attributable to parent			$ 2,953,820
Other comprehensive income (loss) before reclassifications, net of tax			(7,263)
Other comprehensive income (loss), before tax	$ (4,349)	$ 303	(2,276)	$ 6,750	$ 9,706	$ (4,980)
Other comprehensive income (loss), tax	(355)	(566)	(1,195)	(1,698)	(3,987)	1,812
Total other comprehensive income (loss), net of tax	(4,704)	(263)	(3,471)	$ 5,052	5,719	(3,168)
Ending balance, attributable to parent	3,412,915		$ 3,412,915		3,412,915
Effective income tax rate			24.00%	24.00%
Southwest Gas Corporation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance					2,462,794
Beginning balance, attributable to parent			$ 2,527,937
Other comprehensive income (loss), before tax	1,481	2,359	4,987	$ 7,074	16,625	(7,556)
Other comprehensive income (loss), tax	(355)	(566)	(1,195)	(1,698)	(3,987)	1,812
Total other comprehensive income (loss), net of tax	1,126	1,793	3,792	5,376	12,638	(5,744)
Ending balance	2,529,039	2,462,794	2,529,039	2,462,794	2,529,039	2,462,794
Ending balance, attributable to parent	2,529,039		2,529,039		2,529,039
Defined Benefit Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance, before tax			(61,182)
Beginning balance, tax			14,685
Beginning balance			(46,497)
Other comprehensive income (loss), before tax	1,481	1,815	4,442	5,442	15,538	(9,732)
Other comprehensive income (loss), tax	(355)	(435)	(1,066)	(1,306)	(3,728)	2,335
Total other comprehensive income (loss), net of tax	1,126	1,380	3,376	4,136	11,810	(7,397)
Ending balance, before tax	(56,740)		(56,740)		(56,740)
Ending balance, tax	13,619		13,619		13,619
Ending balance	(43,121)		(43,121)		(43,121)
Defined Benefit Plans \| Southwest Gas Corporation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance, attributable to parent, before tax			(61,182)
Beginning balance, attributable to parent, tax			14,685
Beginning balance, attributable to parent			(46,497)
Other comprehensive income (loss), before tax			4,442
Other comprehensive income (loss), tax			(1,066)
Total other comprehensive income (loss), net of tax			3,376
Ending balance, attributable to parent, before tax	(56,740)		(56,740)		(56,740)
Ending balance, attributable to parent, tax	13,619		13,619		13,619
Ending balance, attributable to parent	(43,121)		(43,121)		(43,121)
Amortization of prior service cost
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassification from AOCI, before Tax	44	239	132	719	372	1,007
Reclassification from AOCI, tax	(10)	(56)	(32)	(172)	(90)	(241)
Reclassification from AOCI, net of tax	34	183	100	547	282	766
Other comprehensive income (loss), before tax			132
Other comprehensive income (loss), tax			(32)
Total other comprehensive income (loss), net of tax			100
Amortization of prior service cost \| Southwest Gas Corporation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Other comprehensive income (loss), before tax			132
Other comprehensive income (loss), tax			(32)
Total other comprehensive income (loss), net of tax			100
Amortization of net actuarial loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Other comprehensive income (loss) before reclassifications, before tax					59,176	(57,539)
Other comprehensive income (loss) before reclassifications, net of tax					44,974	(43,730)
Reclassification from AOCI, before Tax	8,705	11,151	26,114	33,448	37,263	42,906
Reclassification from AOCI, tax	(2,089)	(2,677)	(6,267)	(8,028)	(8,942)	(10,298)
Reclassification from AOCI, net of tax	6,616	8,474	19,847	25,420	28,321	32,608
Other comprehensive income (loss), before tax			26,114
Other comprehensive income (loss), tax			(6,267)
Total other comprehensive income (loss), net of tax			19,847
Amortization of net actuarial loss \| Southwest Gas Corporation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Other comprehensive income (loss), before tax			26,114
Other comprehensive income (loss), tax			(6,267)
Total other comprehensive income (loss), net of tax			19,847
Regulatory adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Reclassification from AOCI, before Tax	(7,268)	(9,575)	(21,804)	(28,725)	(81,273)	3,894
Reclassification from AOCI, tax	1,744	2,298	5,233	6,894	19,506	(935)
Reclassification from AOCI, net of tax	(5,524)	(7,277)	(16,571)	(21,831)	(61,767)	2,959
Other comprehensive income (loss), before tax			(21,804)
Other comprehensive income (loss), tax			5,233
Total other comprehensive income (loss), net of tax			(16,571)
Regulatory adjustment \| Southwest Gas Corporation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Other comprehensive income (loss), before tax			(21,804)
Other comprehensive income (loss), tax			5,233
Total other comprehensive income (loss), net of tax			(16,571)
FSIRS
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance, before tax			(545)
Beginning balance, tax			129
Beginning balance			(416)
Reclassification from AOCI, before Tax	0	544	545	1,632	1,087	2,176
Reclassification from AOCI, tax	0	(131)	(129)	(392)	(259)	(523)
Reclassification from AOCI, net of tax	0	413	416	1,240	828	1,653
Other comprehensive income (loss), before tax	0	544	545	1,632	1,087	2,176
Other comprehensive income (loss), tax	0	(131)	(129)	(392)	(259)	(523)
Total other comprehensive income (loss), net of tax	0	413	416	1,240	828	1,653
Ending balance, before tax	0		0		0
Ending balance, tax	0		0		0
Ending balance	0		0		0
FSIRS \| Southwest Gas Corporation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance, attributable to parent, before tax			(545)
Beginning balance, attributable to parent, tax			129
Beginning balance, attributable to parent			(416)
Reclassification from AOCI, before Tax			545
Reclassification from AOCI, tax			(129)
Reclassification from AOCI, net of tax			416
Other comprehensive income (loss), before tax			545
Other comprehensive income (loss), tax			(129)
Total other comprehensive income (loss), net of tax			416
Ending balance, attributable to parent, before tax	0		0		0
Ending balance, attributable to parent, tax	0		0		0
Ending balance, attributable to parent	0		0		0
Foreign Currency Items
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance, before tax			152
Beginning balance, tax			0
Beginning balance			152
Other comprehensive income (loss) before reclassifications, before tax			(7,263)
Other comprehensive income (loss) before reclassifications, net of tax			(7,263)
Ending balance, before tax	(7,111)		(7,111)		(7,111)
Ending balance, tax	0		0		0
Ending balance	(7,111)		(7,111)		(7,111)
AOCI Including Portion Attributable to Noncontrolling Interest
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Other comprehensive income (loss) before reclassifications, net of tax			(3,471)
AOCI Attributable to Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(45,528)	(55,688)	(46,761)	(61,003)	(55,951)
Ending balance	(50,232)	(55,951)	(50,232)	(55,951)	(50,232)	(55,951)
AOCI Attributable to Parent \| Southwest Gas Corporation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(44,247)	(57,552)	(46,913)	(61,135)	(55,759)
Beginning balance, attributable to parent			(46,913)
Ending balance	(43,121)	$ (55,759)	(43,121)	$ (55,759)	(43,121)	$ (55,759)
Ending balance, attributable to parent	$ (43,121)		$ (43,121)		$ (43,121)

Other Comprehensive Income and Accumulated Other Comprehensive Income - Amounts Recognized Before Tax, Defined Benefit Plans (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Equity [Abstract]
Net actuarial loss	$ (372,896)	$ (399,010)
Prior service cost	(1,396)	(1,528)
Less: amount recognized in regulatory assets	317,552	339,356
Recognized in AOCI	$ (56,740)	$ (61,182)

Segment Information - Narratives (Details) - segment	9 Months Ended	12 Months Ended
Segment Information - Narratives (Details) - segment	Sep. 30, 2022	Dec. 31, 2021
Segment Reporting [Abstract]
Number of reportable segments	3	2

Segment Information - Accounts Receivable Not Eliminated During Consolidation (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Centuri
Segment Reporting Information [Line Items]
Centuri accounts receivable for services provided to Southwest	$ 14,393	$ 15,166

- Definition

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(C))
-URI https://asc.fasb.org/extlink&oid=126975872&loc=SL124442552-122756

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124098289&loc=d3e6676-107765

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iv))
-URI https://asc.fasb.org/extlink&oid=126975872&loc=SL124442552-122756

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iv))
-URI https://asc.fasb.org/extlink&oid=126975872&loc=SL124442526-122756

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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+ Details

Segment Information - Schedule of Segment Reporting Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Segment Reporting Information [Line Items]
Total Regulated operations revenues	$ 1,125,588	$ 888,696	$ 3,539,117	$ 2,596,024	$ 4,623,544	$ 3,510,104
Segment net income (loss)	(12,309)	(11,576)	77,294	130,836	147,237	234,380
Revenues from external customers
Segment Reporting Information [Line Items]
Total Regulated operations revenues	1,089,032	861,854	3,440,257	2,521,295	4,497,067	3,402,733
Intersegment revenues
Segment Reporting Information [Line Items]
Total Regulated operations revenues	36,556	26,842	98,860	74,729	126,477	107,371
Segment net income (loss)	(16,775)	(2,572)	(49,962)	(4,545)	(72,193)	(4,477)
Natural Gas Distribution
Segment Reporting Information [Line Items]
Total Regulated operations revenues	303,944	255,848	1,358,425	1,070,576	1,809,639	1,445,066
Segment net income (loss)	(22,199)	(27,544)	87,330	102,584	171,881	182,134
Natural Gas Distribution \| Revenues from external customers
Segment Reporting Information [Line Items]
Total Regulated operations revenues	303,944	255,848	1,358,425	1,070,576	1,809,639	1,445,066
Natural Gas Distribution \| Intersegment revenues
Segment Reporting Information [Line Items]
Total Regulated operations revenues	0	0	0	0	0	0
Utility Infrastructure Services
Segment Reporting Information [Line Items]
Total Regulated operations revenues	758,466	632,848	1,988,433	1,525,448	2,621,646	2,065,038
Segment net income (loss)	14,345	18,540	(4,400)	32,797	3,223	56,723
Utility Infrastructure Services \| Revenues from external customers
Segment Reporting Information [Line Items]
Total Regulated operations revenues	721,910	606,006	1,889,573	1,450,719	2,495,169	1,957,667
Utility Infrastructure Services \| Intersegment revenues
Segment Reporting Information [Line Items]
Total Regulated operations revenues	36,556	26,842	98,860	74,729	126,477	107,371
Pipeline and Storage
Segment Reporting Information [Line Items]
Total Regulated operations revenues	63,178	0	192,259	0	192,259	0
Segment net income (loss)	12,320	0	44,326	0	44,326	0
Pipeline and Storage \| Revenues from external customers
Segment Reporting Information [Line Items]
Total Regulated operations revenues	63,178	0	192,259	0	192,259	0
Pipeline and Storage \| Intersegment revenues
Segment Reporting Information [Line Items]
Total Regulated operations revenues	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details

Business Acquisitions - Narrative (Detail) - USD ($)	3 Months Ended	9 Months Ended
Business Acquisitions - Narrative (Detail) - USD ($)	Sep. 30, 2022	Sep. 30, 2022	Nov. 30, 2021
Business Acquisition [Line Items]
Incurred and expensed acquisition costs	$ 18,500,000	$ 18,500,000
Drum
Business Acquisition [Line Items]
Incurred and expensed acquisition costs	14,000,000	14,000,000
Acquisition-related costs	0	$ 0
Questar Pipelines
Business Acquisition [Line Items]
Acquisition-related costs	$ 0
Certain Members Of Riggs Distler Management \| Drum
Business Acquisition [Line Items]
Ownership percentage by noncontrolling owners	1.42%	1.42%	1.42%

Business Acquisitions - Summary of Assets Acquired and Liabilities Assumed - Drum Acquisition (Detail) - USD ($) $ in Thousands	13 Months Ended
	Sep. 30, 2022	Dec. 31, 2021	Aug. 27, 2021
Fair Values of Assets Acquired and Liabilities Assumed
Goodwill	$ 1,742,967	$ 1,781,332
Drum
Fair Values of Assets Acquired and Liabilities Assumed
Cash and cash equivalents	1,900		$ 1,900
Accounts receivable	60,500		69,100
Contract assets	47,500		40,100
Income taxes receivable, net	400		700
Right of use assets under operating leases	1,500		1,500
Prepaid expenses	5,200		5,200
Property and equipment	119,300		118,100
Intangible assets	303,500		335,000
Goodwill	447,600		446,800
Total assets acquired	987,400		1,018,400
Trade and other payables	46,200		46,200
Finance lease obligations	28,700		27,500
Contract liabilities	12,800		12,700
Operating lease obligations	1,500		1,500
Other liabilities	4,100		5,300
Deferred tax liabilities	70,000		94,800
Total liabilities assumed and noncontrolling interest	163,300		188,000
Net assets acquired	824,100		$ 830,400
Measurement Period Adjustments, Accounts receivable	(8,600)
Measurement Period Adjustments, Contract assets	7,400
Measurement Period Adjustments, Income taxes receivable, net	(300)
Measurement Period Adjustments, Property and equipment	1,200
Measurement Period Adjustments, Intangible assets	(31,500)
Measurement Period Adjustments, Goodwill	800
Measurement Period Adjustments, Total assets	(31,000)
Measurement Period Adjustments, Finance lease obligations	1,200
Measurement Period Adjustments, Finance lease obligations contract liabilities	100
Measurement Period Adjustments, Other liabilities	(1,200)
Measurement Period Adjustments, Deferred tax liabilities	(24,800)
Measurement Period Adjustments, Total liabilities	(24,700)
Measurement Period Adjustments, Net assets acquired	$ (6,300)

Business Acquisitions - Summary of Assets Acquired and Liabilities Assumed - Questar Acquisition (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Business Acquisition [Line Items]
Goodwill	$ 1,742,967	$ 1,781,332
Questar Pipelines
Business Acquisition [Line Items]
Gas plant, net	1,047,400	1,047,400
Other property and investments	51,300	51,300
Cash and cash equivalents	17,600	17,600
Accounts receivable	29,500	26,600
Prepaid and other current assets	27,400	27,400
Deferred charges and other assets	31,100	31,100
Goodwill	958,000	986,200
Deferred income taxes, net	36,300	15,400
Total assets acquired	2,198,600	2,203,000
Long-term debt	449,700	449,700
Accounts payable	7,000	7,000
Deferred purchased gas costs	5,700	5,700
Customer deposits	3,200	3,200
Accrued general taxes	400	400
Accrued interest	4,700	4,700
Other current liabilities	14,500	14,500
Accumulated removal costs	56,600	56,600
Other deferred credits	85,600	85,600
Total liabilities assumed and noncontrolling interest	627,400	627,400
Net assets acquired	1,571,200	$ 1,575,600
Measurement Period Adjustments, Accounts receivable, net of allowances	2,900
Measurement Period Adjustments, Goodwill	(28,200)
Measurement Period Adjustments, Deferred income taxes	20,900
Measurement Period Adjustments, Total assets	(4,400)
Measurement Period Adjustments, Net assets acquired	$ (4,400)

Subsequent Events (Details)	Nov. 04, 2022 USD ($)	Oct. 24, 2022	Sep. 30, 2022 USD ($)
Centuri Credit Facility Amendment \| Letter of Credit \| Centuri
Subsequent Event [Line Items]
Credit facility maximum borrowing capacity			$ 100,000,000
Subsequent Event
Subsequent Event [Line Items]
Amended Cooperation Agreement term, period prior to expiration of advance notice deadline		30 days
Amended Cooperation Agreement, spinoff term, percentage of tender offer closing amount		0.50
Subsequent Event \| Centuri Credit Facility Amendment \| Letter of Credit \| Centuri
Subsequent Event [Line Items]
Credit facility maximum borrowing capacity	$ 125,000,000
Subsequent Event \| Minimum \| Centuri Credit Facility Amendment \| Revolving Credit Facility \| SOFR \| Centuri
Subsequent Event [Line Items]
Debt, basis spread on variable rate	1.00%
Subsequent Event \| Minimum \| Centuri Credit Facility Amendment \| Revolving Credit Facility \| CDOR \| Centuri
Subsequent Event [Line Items]
Debt, basis spread on variable rate	0.00%
Subsequent Event \| Maximum \| Centuri Credit Facility Amendment \| Revolving Credit Facility \| SOFR \| Centuri
Subsequent Event [Line Items]
Debt, basis spread on variable rate	2.50%
Subsequent Event \| Maximum \| Centuri Credit Facility Amendment \| Revolving Credit Facility \| CDOR \| Centuri
Subsequent Event [Line Items]
Debt, basis spread on variable rate	1.50%