CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021
OPERATING REVENUES
Utility	$ 463,474	$ 310,167	$ 737,909	$ 505,896
Nonutility	448,842	492,020	850,249	750,596
Total operating revenues	912,316	802,187	1,588,158	1,256,492
Natural gas purchases:
Gas purchases - Related parties	1,883	1,730	3,729	3,464
Operation and maintenance	85,786	110,265	154,770	183,901
Regulatory rider expenses	30,910	18,413	47,581	29,114
Depreciation and amortization	31,435	26,848	61,828	54,210
Total operating expenses	773,441	600,979	1,292,398	943,804
OPERATING INCOME	138,875	201,208	295,760	312,688
Other income, net	4,127	5,007	8,263	9,124
Interest expense, net of capitalized interest	18,926	20,153	38,403	39,939
INCOME BEFORE INCOME TAXES AND EQUITY IN EARNINGS OF AFFILIATES	124,076	186,062	265,620	281,873
Income tax provision	28,810	39,057	59,617	56,498
Equity in earnings of affiliates	769	2,804	1,344	5,479
NET INCOME	$ 96,035	$ 149,809	$ 207,347	$ 230,854
EARNINGS PER COMMON SHARE
Basic (usd per share)	$ 1.00	$ 1.56	$ 2.16	$ 2.40
Diluted (usd per share)	$ 1.00	$ 1.55	$ 2.15	$ 2.39
WEIGHTED AVERAGE SHARES OUTSTANDING
Basic (in shares)	96,068	96,248	96,006	96,181
Diluted (in shares)	96,516	96,618	96,480	96,598
Regulated
Natural gas purchases:
Gas purchases - Utility and Nonutility	$ 212,892	$ 113,235	$ 335,161	$ 169,380
Unregulated
Natural gas purchases:
Gas purchases - Utility and Nonutility	$ 410,535	$ 330,488	$ 689,329	$ 503,735