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CONTINGENCIES, COMMITMENTS, AND GUARANTEES - Nuclear Fuel Disposal Costs and Nuclear Insurance (Details) $ in Millions | 12 Months Ended | 108 Months Ended
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Dec. 31, 2024 USD ($) plant | Dec. 31, 2019 USD ($)
Jointly Owned Utility Plant Interests [Line Items] |  |
Maximum fund for public liability claims arising from a single nuclear incident under price - anderson amendments act | $ 16,300 |
Maximum insurance coverage provided by American Nuclear Insurers to each nuclear plant | 500 |
Maximum amount that a company could be assessed per incident for each licensed reactor | 166 |
Maximum aggregate amount that a reactor can assess in a calendar period for each incident | $ 25 |
Block period considered for inflation adjustment against maximum assessment per reactor | 5 years |
Maximum deductible waiting period | 182 days |
Maximum coverage per occurrence per unit limit to obtain replacement power | $ 490 |
Aggregate payment for claims resulting from terrorist acts in one year period | $ 3,200 |
Alabama Power and Georgia Power |  |
Jointly Owned Utility Plant Interests [Line Items] |  |
Number of nuclear fuel plants | plant | 3 |
Maximum property damage insurance provided to nuclear generating facilities | $ 1,500 |
Maximum additional coverage provided for losses under excess insurance | 1,250 |
Maximum additional coverage provided for losses under excess insurance, non-nuclear losses | $ 750 |
Elected deductible waiting period | 84 days |
Alabama Power |  |
Jointly Owned Utility Plant Interests [Line Items] |  |
Maximum assessment, excluding any applicable state premium taxes | $ 332 |
Maximum aggregate amount to be paid in one year | 49 |
Current maximum annual assessments under NEIL policies | 60 |
Alabama Power | Positive Outcome of Litigation |  |
Jointly Owned Utility Plant Interests [Line Items] |  |
Outstanding claims |  | $ 100
Georgia Power |  |
Jointly Owned Utility Plant Interests [Line Items] |  |
Maximum assessment, excluding any applicable state premium taxes | 473 |
Maximum aggregate amount to be paid in one year | 71 |
Current maximum annual assessments under NEIL policies | $ 80 |
Georgia Power | Court Of Federal Claims |  |
Jointly Owned Utility Plant Interests [Line Items] |  |
Litigation settlement |  | $ 121

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