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Statements of Common Stockholders' Equity - MPC - USD ($) shares in Millions, $ in Millions | Total | Common Stock | Paid-In Capital | Retained Earnings | Accumulated Other Comprehensive Income (Loss) | Mississippi Power | Mississippi Power Common Stock | Mississippi Power Paid-In Capital | Mississippi Power Retained Earnings | Mississippi Power Accumulated Other Comprehensive Income (Loss)
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Beginning balance (in shares) at Dec. 31, 2020 |  | 1,058 |  |  |  |  | 1 |  |  |
Beginning balance at Dec. 31, 2020 |  |  |  |  |  | $ 1,742 | $ 38 | $ 4,460 | $ (2,754) | $ (2)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |  |  |
Net income | $ 2,393 |  |  |  |  | 159 |  |  | 159 |
Capital contributions from parent company |  |  |  |  |  | 122 |  | 122 |  |
Other comprehensive income (loss) | 158 |  |  |  | $ 158 | 1 |  |  |  | 1
Cash dividends on common stock | (2,777) |  |  | $ (2,777) |  | (157) |  |  | (157) |
Other | (7) |  | $ (8) | 2 |  |  |  |  | (1) | 1
Ending balance (in shares) at Dec. 31, 2021 |  | 1,061 |  |  |  |  | 1 |  |  |
Ending balance at Dec. 31, 2021 |  |  |  |  |  | 1,867 | $ 38 | 4,582 | (2,753) | 0
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |  |  |
Net income | 3,524 |  |  |  |  | 164 |  |  | 164 |
Capital contributions from parent company |  |  |  |  |  | 70 |  | 70 |  |
Other comprehensive income (loss) | 71 |  |  |  | 71 |  |  |  |  |
Cash dividends on common stock | (2,907) |  |  | (2,907) |  | (170) |  |  | (170) |
Other | (6) |  | 9 | (8) | (1) |  |  |  |  |
Ending balance (in shares) at Dec. 31, 2022 |  | 1,090 |  |  |  |  | 1 |  |  |
Ending balance at Dec. 31, 2022 | 30,408 |  |  |  |  | 1,931 | $ 38 | 4,652 | (2,759) | 0
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |  |  |
Net income | 3,976 |  |  |  |  | 188 |  |  | 188 |
Capital contributions from parent company |  |  |  |  |  | 69 |  | 69 |  |
Other comprehensive income (loss) | (10) |  |  |  | $ (10) |  |  |  |  |
Cash dividends on common stock | (3,035) |  |  | (3,035) |  | (185) |  |  | (185) |
Other | (5) |  | $ (1) | $ 3 |  |  |  |  |  |
Ending balance (in shares) at Dec. 31, 2023 |  | 1,092 |  |  |  |  | 1 |  |  |
Ending balance at Dec. 31, 2023 | $ 31,444 |  |  |  |  | $ 2,003 | $ 38 | $ 4,721 | $ (2,756) | $ 0

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