Consolidated Statements Of Revenues, Expenses, And Patronage Capital - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Statement [Abstract]
Operating Revenues	$ 1,111,872	$ 1,082,391	$ 1,005,917
Type of Revenue [Extensible List]	us-gaap:ElectricityMember	us-gaap:ElectricityMember	us-gaap:ElectricityMember
Operating Expenses:
Fuel	$ 193,035	$ 193,081	$ 193,599
Purchased power	362,257	312,833	462,526
Transmission	194,140	173,492	151,778
Deferred energy	70,104	114,538	(78,831)
Operations and maintenance	98,699	95,165	91,360
Administrative and general	49,565	41,841	42,111
Depreciation and amortization	70,258	69,573	69,167
Amortization of regulatory asset/(liability), net	13,301	2,080	(960)
Accretion of asset retirement obligations	6,289	6,077	5,873
Taxes, other than income taxes	9,353	8,614	8,784
Total Operating Expenses	1,067,001	1,017,294	945,407
Operating Margin	44,871	65,097	60,510
Other income (expense), net	(41)	(284)	1,967
Investment income	23,721	9,472	4,709
Interest charges, net	(56,526)	(61,332)	(55,265)
Income taxes (expense)/benefit	(65)	(110)	(151)
Net Margin including Non-controlling interest	11,960	12,843	11,770
Non-controlling interest	(188)	(290)	(465)
Net Margin attributable to ODEC	11,772	12,553	11,305
Patronage Capital - Beginning of Period	488,635	476,082	464,777
Patronage Capital - End of Period	$ 500,407	$ 488,635	$ 476,082