CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
OPERATING REVENUES
Utility	$ 1,018,482	$ 1,011,284	$ 1,127,417
Nonutility	778,057	951,710	1,778,562
Total operating revenues	1,796,539	1,962,994	2,905,979
Natural gas purchases:
Related parties	7,147	7,206	7,395
Operation and maintenance	394,636	373,568	361,866
Regulatory rider expenses	60,327	50,542	59,437
Depreciation and amortization	166,567	152,941	129,249
Total operating expenses	1,338,435	1,555,994	2,499,504
OPERATING INCOME	458,104	407,000	406,475
Other income, net	41,553	26,083	22,295
Interest expense, net of capitalized interest	130,275	123,014	85,830
INCOME BEFORE INCOME TAXES AND EQUITY IN EARNINGS OF AFFILIATES	369,382	310,069	342,940
Income tax provision	84,906	49,275	76,195
Equity in earnings of affiliates	5,299	3,930	8,177
NET INCOME	$ 289,775	$ 264,724	$ 274,922
EARNINGS PER COMMON SHARE
Basic (usd per share)	$ 2.94	$ 2.73	$ 2.86
Diluted (usd per share)	$ 2.92	$ 2.71	$ 2.85
WEIGHTED AVERAGE SHARES OUTSTANDING
Basic (in shares)	98,634	97,028	96,100
Diluted (in shares)	99,289	97,627	96,488
Utility
Natural gas purchases:
Gas purchases - Utility and Nonutility	$ 405,332	$ 416,158	$ 547,901
Nonutility
Natural gas purchases:
Gas purchases - Utility and Nonutility	$ 304,426	$ 555,579	$ 1,393,656