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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, 2018 |  | 1,035 |  |  |  |  | 1 |  |  |
Beginning balance at Dec. 31, 2018 | $ 29,039 | $ 5,164 | $ 11,094 | $ 8,706 | $ (203) | $ 1,609 | $ 38 | $ 4,546 | $ (2,971) | $ (4)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |  |  |
Consolidated Net Income | 4,739 |  |  |  |  | 139 |  |  | 139 |
Return of capital to parent company |  |  |  |  |  | (150) |  | (150) |  |
Capital contributions from parent company |  |  |  |  |  | 53 |  | 53 |  |
Other comprehensive income (loss) | (118) |  |  |  | (118) | 1 |  |  |  | 1
Cash dividends on common stock | (2,570) |  |  | (2,570) |  |  |  |  |  |
Other | 18 |  | 21 | 2 |  |  |  |  |  |
Ending balance (in shares) at Dec. 31, 2019 |  | 1,054 |  |  |  |  | 1 |  |  |
Ending balance at Dec. 31, 2019 | 31,759 | $ 5,257 | 11,734 | 10,877 | (321) | 1,652 | $ 38 | 4,449 | (2,832) | (3)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |  |  |
Consolidated Net Income | 3,119 |  |  |  |  | 152 |  |  | 152 |
Return of capital to parent company |  |  |  |  |  | (74) |  | (74) |  |
Capital contributions from parent company |  |  |  |  |  | 86 |  | 86 |  |
Other comprehensive income (loss) | (75) |  |  |  | (75) | 1 |  |  |  | 1
Cash dividends on common stock | (2,685) |  |  | (2,685) |  | (74) |  |  | (74) |
Other | (12) |  | (10) |  | 1 | (1) |  | (1) |  |
Ending balance (in shares) at Dec. 31, 2020 |  | 1,058 |  |  |  |  | 1 |  |  |
Ending balance at Dec. 31, 2020 | 32,234 | $ 5,268 | 11,834 | 11,311 | (395) | 1,742 | $ 38 | 4,460 | (2,754) | (2)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |  |  |
Consolidated 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 | $ 32,276 | $ 5,279 | $ 11,950 | $ 10,929 | $ (237) | $ 1,867 | $ 38 | $ 4,582 | $ (2,753) | $ 0

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