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

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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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Represents the number of electric distribution cooperative members.

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No definition available.

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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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Rate Management Program, Amount Expected To Be Collected

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

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No definition available.

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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, 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, classified as current.

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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	1 Months Ended	6 Months Ended		12 Months Ended
Revenue Recognition - Narrative (Details) $ in Thousands	Mar. 31, 2026 USD ($)	Jun. 30, 2026 USD ($) member service	Jun. 30, 2025 USD ($)	Dec. 31, 2026	Dec. 31, 2025 USD ($)	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					1.10
Refund liability		$ 22,000	$ 6,250		$ 70,632
Vogtle New Units
Revenue Recognition
Refund liability		75,920
Rate management program, additional collection period						5 years
Rate management program, billing period						5 years
Amounts billed under additional rate management program		33,259	$ 48,464
Cumulative recovery of financing costs		369,102
Smarr Combined Cycle Project
Revenue Recognition
Rate management program, additional collection period	3 years
Rate management program, billing period	3 years
Amounts billed under additional rate management program		1,600
Rate management program, amount expected to be collected	$ 32,200
Sales to members
Revenue Recognition
Receivables from contracts		221,358			237,834
Sales to members \| Receivable from U.S. Government, Nuclear Production Tax Credit
Revenue Recognition
Long-term receivables		53,566			53,566
Sales to non-members \| Receivable from U.S. Government, Nuclear Production Tax Credit
Revenue Recognition
Current receivables		126,517			126,517
Sales to non-members \| Sale of Bobby C. Smith Jr. Deferring Members' Output
Revenue Recognition
Receivables from contracts		$ 178,375			$ 159,225
Forecast
Revenue Recognition
Minimum margins to interest ratio				1.10