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v3.23.2

Segment and Related Information - Narrative (Details) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 USD ($) state | Jun. 30, 2022 USD ($) | Jun. 30, 2023 USD ($) state segment | Jun. 30, 2022 USD ($)
Segment Reporting Information [Line Items] |  |  |  |
Number of states in which entity operates | state | 3 |  | 3 |
Operating revenues | $ 5,532 | $ 6,226 | $ 11,777 | $ 12,486
SOUTHERN POWER CO |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | $ 365 | 731 | $ 769 | 1,146
SOUTHERN Co GAS |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Number of states in which entity operates | state | 4 |  | 4 |
Operating revenues | $ 834 | 1,063 | $ 2,664 | 3,105
Number of reportable segments | segment |  |  | 3 |
SOUTHERN Co GAS | Southern Natural Gas Company, LLC |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Ownership percentage, equity method investment | 50.00% |  | 50.00% |
SOUTHERN Co GAS | Dalton Pipeline |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Ownership percentage, equity method investment | 50.00% |  | 50.00% |
Traditional Electric Operating Companies | Wholesale revenues, affiliates | SOUTHERN POWER CO |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | $ 116 | 232 | $ 251 | 337
Traditional Electric Operating Companies | Natural Gas | SOUTHERN Co GAS |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating revenues | $ 0 | $ 0 | $ 0 | $ 0

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