CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
CASH FLOW FROM OPERATING ACTIVITIES:
Net income	$ 112,886	$ 118,216	$ 211,317	$ 200,023
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	164,870	147,881	320,226	273,308
Deferred income taxes	31,121	31,831	53,452	49,554
Changes in current assets and liabilities:
Accounts receivable, net of allowances	(9,746)	(2,612)	(61,379)	(5,770)
Accrued utility revenue	43,300	42,300	(900)	(700)
Deferred purchased gas costs	53,595	(43,341)	38,445	5,128
Accounts payable	(47,198)	(48,155)	(908)	8,088
Accrued taxes	9,019	(2,272)	16,534	3,123
Other current assets and liabilities	78,538	54,988	97,687	17,721
Gains on sale of equipment	(309)	(831)	(4,951)	(2,284)
Changes in undistributed stock compensation	4,332	4,702	6,526	7,513
Equity AFUDC	(2,181)	(1,967)	(4,375)	(5,008)
Changes in deferred charges and other assets	(8,268)	(15,870)	(13,449)	(16,486)
Changes in other liabilities and deferred credits	(54,819)	(6,454)	(61,129)	26,040
Net cash provided by operating activities	375,140	278,416	597,096	560,250
CASH FLOW FROM INVESTING ACTIVITIES:
Construction expenditures and property additions	(423,435)	(471,578)	(890,005)	(898,481)
Acquisition of businesses, net of cash acquired	(250)	(19,533)	(28,355)	(266,697)
Changes in customer advances	4,098	9,483	13,616	14,788
Other	5,045	1,159	19,039	2,936
Net cash used in investing activities	(414,542)	(480,469)	(885,705)	(1,147,454)
CASH FLOW FROM FINANCING ACTIVITIES:
Issuance of common stock, net	55,498	102,743	110,701	388,006
Dividends paid	(61,445)	(56,738)	(120,834)	(107,993)
Issuance of long-term debt, net	620,303	421,594	730,305	531,368
Retirement of long-term debt	(117,536)	(53,604)	(277,721)	(190,586)
Change in credit facility and commercial paper	(150,000)	(104,000)	(46,000)	(2,000)
Change in short-term debt	(153,000)	(152,000)	58,000	(22,500)
Principal payments on finance lease obligations	(102)	(107)	(207)	(439)
Withholding remittance - share-based compensation	(2,736)	(1,856)	(2,738)	(2,112)
Other	(1,358)	(966)	(1,668)	(2,812)
Net cash provided by financing activities	189,624	155,066	449,838	590,932
Effects of currency translation on cash and cash equivalents	(170)	72	(84)	(12)
Change in cash and cash equivalents	150,052	(46,915)	161,145	3,716
Cash and cash equivalents at beginning of period	49,539	85,361	38,446	34,730
Cash and cash equivalents at end of period	199,591	38,446	199,591	38,446
SUPPLEMENTAL INFORMATION:
Interest paid, net of amounts capitalized	51,430	49,996	103,692	96,476
Income taxes paid (received), net	(19,410)	1,832	(18,490)	(13,454)
Southwest Gas Corporation
CASH FLOW FROM OPERATING ACTIVITIES:
Net income	95,541	106,758	151,954	152,629
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	117,923	106,955	226,588	201,146
Deferred income taxes	18,186	28,183	23,684	43,811
Changes in current assets and liabilities:
Accounts receivable, net of allowances	57,047	46,626	(316)	(9,787)
Accrued utility revenue	43,300	42,300	(900)	(700)
Deferred purchased gas costs	53,595	(43,341)	38,445	5,128
Accounts payable	(53,712)	(74,787)	(6,398)	716
Accrued taxes	17,746	(52)	26,693	(6,008)
Other current assets and liabilities	71,512	74,589	86,094	7,511
Changes in undistributed stock compensation	3,494	3,760	4,880	5,895
Equity AFUDC	(2,181)	(1,967)	(4,375)	(5,008)
Changes in deferred charges and other assets	(13,689)	(20,336)	(25,120)	(21,895)
Changes in other liabilities and deferred credits	(55,173)	(6,836)	(61,698)	25,356
Net cash provided by operating activities	353,589	261,852	459,531	398,794
CASH FLOW FROM INVESTING ACTIVITIES:
Construction expenditures and property additions	(354,501)	(365,251)	(767,998)	(762,121)
Changes in customer advances	4,098	9,483	13,616	14,788
Other	100	(49)	54	(813)
Net cash used in investing activities	(350,303)	(355,817)	(754,328)	(748,146)
CASH FLOW FROM FINANCING ACTIVITIES:
Contributions from parent	99,500	102,092	157,344	159,045
Dividends paid	(51,100)	(46,300)	(100,700)	(90,300)
Issuance of long-term debt, net	446,508	297,222	446,508	297,222
Change in credit facility and commercial paper	(150,000)	(104,000)	(46,000)	(2,000)
Change in short-term debt	(194,000)	(152,000)	0	0
Withholding remittance - share-based compensation	(2,736)	(1,856)	(2,738)	(2,111)
Other	(1,163)	(712)	(1,276)	(961)
Net cash provided by financing activities	147,009	94,446	453,138	360,895
Change in cash and cash equivalents	150,295	481	158,341	11,543
Cash and cash equivalents at beginning of period	40,489	31,962	32,443	20,900
Cash and cash equivalents at end of period	190,784	32,443	190,784	32,443
SUPPLEMENTAL INFORMATION:
Interest paid, net of amounts capitalized	46,576	42,853	92,381	83,206
Income taxes paid (received), net	$ (22,962)	$ (22)	$ (22,262)	$ (16,764)