Consolidated Statements of Revenues and Expenses (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating revenues:
Total operating revenues	$ 536,314	$ 389,453
Operating expenses:
Fuel	167,046	133,168
Production	118,090	93,467
Depreciation and amortization	94,105	72,674
Purchased power	19,220	17,630
Accretion	17,622	15,508
Total operating expenses	416,083	332,447
Operating margin	120,231	57,006
Other income:
Investment income	17,052	16,382
Other	2,804	2,925
Total other income	19,856	19,307
Interest charges:
Interest expense	129,391	123,707
Allowance for debt funds used during construction	(34,107)	(74,430)
Amortization of debt discount and expense	2,704	2,626
Net interest charges	97,988	51,903
Net margin	42,099	24,410
Sales to members
Operating revenues:
Total operating revenues	535,370	387,653
Sales to non-members
Operating revenues:
Total operating revenues	$ 944	$ 1,800