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Consolidated Statements of Common Stockholders' Equity - GAS - USD ($) $ in Millions | Total | Paid-In Capital | Retained Earnings | Accumulated Other Comprehensive Income (Loss) | Southern Company Gas | Southern Company Gas Paid-In Capital | Southern Company Gas Retained Earnings | Southern Company Gas Accumulated Other Comprehensive Income (Loss)
--- | --- | --- | --- | --- | --- | --- | --- | ---
Beginning balance at Dec. 31, 2021 |  |  |  |  | $ 9,916 | $ 10,024 | $ (132) | $ 24
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |
Net Income | $ 3,428 |  |  |  | 572 |  | 572 |
Capital contributions from parent company |  |  |  |  | 421 | 421 |  |
Other comprehensive income (loss) | 71 |  |  | $ 71 | 7 |  |  | 7
Cash dividends on common stock | (2,907) |  | $ (2,907) |  | (519) |  | (519) |
Other | (6) | $ 9 | (8) | (1) |  |  |  |
Ending balance at Dec. 31, 2022 |  |  |  |  | 10,397 | 10,445 | (79) | 31
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |
Net Income | 3,849 |  |  |  | 615 |  | 615 |
Capital contributions from parent company |  |  |  |  | 391 | 391 |  |
Other comprehensive income (loss) | (10) |  |  | (10) | (15) |  |  | (15)
Cash dividends on common stock | (3,035) |  | (3,035) |  | (585) |  | (585) |
Other | (5) | (1) | 3 |  |  |  |  |
Ending balance at Dec. 31, 2023 | 31,444 |  |  |  | 10,803 | 10,836 | (49) | 16
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |
Net Income | 4,260 |  |  |  | 740 |  | 740 |
Capital contributions from parent company |  |  |  |  | 27 | 27 |  |
Other comprehensive income (loss) | 99 |  |  | 99 | 32 |  |  | 32
Cash dividends on common stock | (3,133) |  | (3,133) |  | (605) |  | (605) |
Other | 19 | $ 19 | $ 0 | $ 0 | (1) |  | (1) |
Ending balance at Dec. 31, 2024 | $ 33,208 |  |  |  | $ 10,996 | $ 10,863 | $ 85 | $ 48

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