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v3.25.3

Revenue from Contracts with Customers and Lease Income - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2025 | Dec. 31, 2024
Disaggregation of Revenue [Line Items] |  |  |
Contract liabilities | $ 185 | $ 185 | $ 140
Contract assets | 443 | 443 | 323
Revenue from contracts with customers recognized | 20 | 92 |
GEORGIA POWER CO |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Contract liabilities | 72 | 72 | 34
Contract assets | 283 | 283 | 184
Revenue from contracts with customers recognized | 8 | 24 |
SOUTHERN Co GAS |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Contract liabilities | 0 | 0 | 3
Contract assets | 74 | 74 | 72
Revenue from contracts with customers recognized | 0 | 0 |
ALABAMA POWER CO |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Contract liabilities | 15 | 15 | 11
Contract assets | 8 | 8 | 3
Revenue from contracts with customers recognized | 0 | 0 |
MISSISSIPPI POWER CO |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Contract liabilities | 2 | 2 | 0
Contract assets | 0 | 0 | 0
Revenue from contracts with customers recognized | 0 | 0 |
SOUTHERN POWER CO |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Contract liabilities | 2 | 2 | 2
Contract assets | 0 | 0 | 0
Revenue from contracts with customers recognized | 0 | $ 0 |
Retail Customer Fixed Bill Programs | GEORGIA POWER CO |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Contract term |  | 1 year |
Energy Efficiency Enhancement And Upgrade | SOUTHERN Co GAS |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Contract liabilities | 68 | $ 68 |
Unregulated Distributed Generation |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Contract liabilities | 96 | 96 | 95
Contract assets | $ 77 | $ 77 | $ 67

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