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REGULATORY MATTERS - APC Rate ECR (Details) - Alabama Power $ in Millions |  | 1 Months Ended | 12 Months Ended
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May 08, 2024 USD ($) $ / KWH_Kilowatt_hour | Jan. 31, 2026 $ / KWH_Kilowatt_hour | Jan. 31, 2025 USD ($) $ / KWH_Kilowatt_hour | Dec. 31, 2023 USD ($) $ / KWH_Kilowatt_hour | Dec. 31, 2022 USD ($) $ / KWH_Kilowatt_hour | Nov. 30, 2022 $ / KWH_Kilowatt_hour | Aug. 31, 2022 USD ($) $ / KWH_Kilowatt_hour | Jul. 31, 2022 $ / KWH_Kilowatt_hour | Dec. 31, 2024 USD ($) $ / KWH_Kilowatt_hour
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |  |  |
Current billing rates under rate ECR (usd per KWH) | $ / KWH_Kilowatt_hour | 0.03015 |  |  | 0.03270 | 3.510 | 2.557 | 2.557 | 1.960 | 0.05910
Current billing rates under rate ECR, amount | $ 135 |  |  | $ 126 | $ 500 |  | $ 310 |  |
Over (under) recovered fuel cost |  |  |  | $ (246) |  |  |  |  | $ (29)
Scenario, Forecast |  |  |  |  |  |  |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |  |  |  |  |  |  |
Current billing rates under rate ECR (usd per KWH) | $ / KWH_Kilowatt_hour |  | 0.05910 | 0.02600 |  |  |  |  |  |
Current billing rates under rate ECR, amount |  |  | $ 218 |  |  |  |  |  |

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- Details
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