Consolidated Statements Of Operations And Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Consolidated Statements Of Operations [Abstract]
Operating revenues	$ 612,069	$ 726,450
Operating expenses:
Operations and maintenance	136,900	137,994
Purchased gas	129,675	256,315
Depreciation	88,716	82,923
Amortization	1,088	871
Taxes other than income taxes	25,024	22,878
Total operating expenses	381,403	500,981
Operating income	230,666	225,469
Other expense (income):
Interest expense	73,273	72,668
Interest income	(989)	(819)
Allowance for funds used during construction	(4,681)	(5,688)
Gain on sale of other assets	(91,625)	(249)
Other	(442)	(240)
Income before income taxes	255,130	159,797
Income tax benefit	(10,642)	(31,637)
Net income	265,772	191,434
Comprehensive income	$ 265,772	$ 191,434
Net income per common share:
Basic	$ 0.97	$ 0.72
Diluted	$ 0.97	$ 0.72
Average common shares outstanding during the period:
Basic	273,377	264,192
Diluted	273,738	264,751