Represents the cumulative amount recovered from members pursuant to rate management programs.

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Litigation Settlement, Receivable

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Represents the ratio of margins for interest to total interest charges for a given period.

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Represents the minimum margins to interest ratio required to be maintained under first mortgage indenture by the entity.

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No definition available.

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Represents the number of electric distribution cooperative members.

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Represents the number of services provided.

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No definition available.

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The period of additional collections made to recover future expense on a current basis.

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No definition available.

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The amount of billing made by participating members under rate management program.

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Rate Management Program, Billing Period

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No definition available.

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Amount, before allowance for credit loss, of right to consideration in exchange for good or service transferred to customer, when right is conditioned on something other than passage of time.

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Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Revenue Recognition - Narrative (Details) $ in Thousands	6 Months Ended		12 Months Ended
Revenue Recognition - Narrative (Details) $ in Thousands	Jun. 30, 2025 USD ($) member service	Jun. 30, 2024 USD ($)	Dec. 31, 2025	Dec. 31, 2024 USD ($)	Dec. 31, 2018
Revenue Recognition
Number of electric distribution cooperative members \| member	38
Number of services provided \| service	2
Margins for interest ratio	1.10
Minimum margins to interest ratio				1.14
Refund liability	$ 6,250	$ 12,900		$ 55,914
Plant Hatch And Plant Vogtle \| Litigation Nuclear Fuel Disposal Cost \| Settled Litigation
Revenue Recognition
Litigation settlement, receivable				39,433
Vogtle New Units
Revenue Recognition
Refund liability	153,527
Rate management program, additional collection period					5 years
Rate management program, billing period					5 years
Amounts billed under additional rate management program	48,464	$ 60,818
Cumulative recovery of financing costs	369,102
Sales to members
Revenue Recognition
Receivables from contracts	209,827			177,790
Sales to non-members \| Sale of Bobby C. Smith Jr. Deferring Members' Output
Revenue Recognition
Receivables from contracts	$ 61,325			$ 68,791
Forecast
Revenue Recognition
Minimum margins to interest ratio			1.10