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Regulatory Matters - APC Certificate of Convenience and Necessity (Details) - USD ($) $ in Millions | Jun. 30, 2023 | Dec. 31, 2022 | Dec. 31, 2020
--- | --- | --- | ---
Public Utilities, General Disclosures [Line Items] |  |  |
Construction work in progress | $ 11,992 | $ 10,896 |
Plant in service, net of depreciation | 83,352 | 82,232 |
ALABAMA POWER CO |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Construction work in progress | 1,600 | 1,526 |
Plant in service, net of depreciation | 23,234 | $ 23,002 |
ALABAMA POWER CO | Plant Barry Unit 8 |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Estimated in-service cost |  |  | $ 652
Construction work in progress | 568 |  |
Construction in progress, work in progress amount | 563 |  |
Plant in service, net of depreciation | $ 5 |  |

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