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Regulatory Matters - GPC Nuclear Construction Regulatory Matters (Details) - Plant Vogtle Units 3 And 4 - GEORGIA POWER CO $ in Millions |  |  |  |  |  |  | 6 Months Ended | 12 Months Ended | 12003 Months Ended |  |  |
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Feb. 16, 2023 USD ($) | Jan. 01, 2023 USD ($) | Jan. 01, 2021 | Jan. 01, 2020 | Jan. 11, 2018 USD ($) | Jan. 01, 2016 | Jun. 30, 2023 USD ($) | Jun. 30, 2022 USD ($) claim | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2009 USD ($) | Dec. 31, 2022 USD ($) | Jun. 30, 2021 report | Jun. 30, 2018 USD ($) | Dec. 31, 2013
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated in-service capital cost |  |  |  |  |  |  |  |  |  |  |  | $ 4,418 |  |  |  |
Financing costs collected, net of tax |  |  |  |  |  |  | $ 3,000 |  |  |  |  |  |  |  |  |
Increase in tariff |  | $ 36 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional construction capital costs |  |  |  |  | $ 3,300 |  |  |  |  |  |  |  | $ 345 |  |  |
Payments for contractor settlement agreement |  |  |  |  | 300 |  |  |  |  |  |  |  |  |  |  |
Amendment to estimated in-service capital cost |  |  |  |  | $ 5,680 |  |  |  |  |  |  |  |  |  |  |
Retail rate of return on common equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10.95%
Public utilities, approved return on equity percentage |  |  | 5.30% | 8.30% |  | 10.00% |  |  |  |  |  |  |  |  |  |
Public utilities, approved return on equity, monthly percentage decrease |  |  |  |  |  |  | 0.10% |  |  |  |  |  |  |  |  |
Return on equity reduction, negative impact on earnings |  |  |  |  |  |  |  |  |  |  | $ 300 |  |  |  |  |
Increase to base capital cost forecast not seeking recovery |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 700 |
Twenty Fourth Vogtle Construction Monitoring Report |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cost settlement agreement revised forecast, net of payments |  |  |  |  |  |  | $ 7,300 |  |  |  |  |  |  |  |  |
Twenty Fifth Vogtle Construction Monitoring Report |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of approved construction management reports | report |  |  |  |  |  |  |  |  |  |  |  |  |  | 25 |  |
Requested capital construction costs |  |  |  |  |  |  | 7,900 |  |  |  |  |  |  |  |  |
Guarantor obligations |  |  |  |  |  |  | 1,700 |  |  |  |  |  |  |  |  |
Customer refund |  |  |  |  |  |  | 188 |  |  |  |  |  |  |  |  |
Twenty Sixth Vogtle Construction Monitoring Report |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested capital construction costs |  |  |  |  |  |  |  | $ 1,100 |  |  |  |  |  |  |  |
Number of additional reports reviewed | claim |  |  |  |  |  |  |  | 2 |  |  |  |  |  |  |  |
Twenty Seventh Vogtle Construction Monitoring Report |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested capital construction costs | $ 461 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Twenty Ninth Vogtle Construction Monitoring Report |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Requested capital construction costs |  |  |  |  |  |  | $ 390 |  |  |  |  |  |  |  |  |
Scenario, Forecast |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Return on equity reduction, negative impact on earnings |  |  |  |  |  |  |  |  | $ 60 | $ 290 |  |  |  |  |  |

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