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RETIREMENT BENEFITS - Changes in Regulatory Assets (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | $ 6,523 |  |  |
Total Stockholders' Equity (See accompanying statements) | 36,674 | $ 35,225 | $ 34,532 | $ 32,276
Total other comprehensive income (loss) | 99 | (10) | 71 |
Ending balance | 7,041 | 6,523 |  |
Regulatory asset |  | 66 | 216 |
Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Total Stockholders' Equity (See accompanying statements) | (32) | (56) | (18) | (76)
Total other comprehensive income (loss) | 24 | (38) | 58 |
Pension plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 2,913 |  |  |
Ending balance | 2,658 | 2,913 |  |
Pension plans | Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 2,913 | 2,371 |  |
Total Stockholders' Equity (See accompanying statements) | 52 | 79 | 24 |
Reclassification adjustments | 2 | (7) |  |
Total other comprehensive income (loss) | (27) | 55 |  |
Ending balance | 2,658 | 2,913 | 2,371 |
Pension plans | Pension and Other Postretirement Benefit Plans | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | (56) | (34) |  |
Total other comprehensive income (loss) | (255) | 542 |  |
Pension plans | Net loss |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | (29) | 62 |  |
Reclassification adjustments | 1 | (8) |  |
Pension plans | Net loss | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | (199) | 576 |  |
Reclassification adjustments | (55) | (33) |  |
Pension plans | Change in prior service costs |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 1 | 1 |  |
Pension plans | Change in prior service costs | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | (1) | (1) |  |
Pension plans | Amortization of regulatory assets | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 0 | 0 |  |
Other Postretirement Benefits Plan |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 203 |  |  |
Reclassification adjustments | 3 | 7 |  |
Ending balance | 189 | 203 |  |
Other Postretirement Benefits Plan | Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | (208) | (136) |  |
Total Stockholders' Equity (See accompanying statements) | (14) | (9) | (4) |
Total other comprehensive income (loss) | (5) | (5) |  |
Ending balance | (189) | (208) | (136) |
Other Postretirement Benefits Plan | Pension and Other Postretirement Benefit Plans | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 11 | 5 |  |
Total other comprehensive income (loss) | 19 | (72) |  |
Other Postretirement Benefits Plan | Net loss |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | (8) | (12) |  |
Other Postretirement Benefits Plan | Net loss | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | (8) | 77 |  |
Reclassification adjustments | 13 | 6 |  |
Other Postretirement Benefits Plan | Change in prior service costs | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | (2) | (1) |  |
Other Postretirement Benefits Plan | Amortization of regulatory assets | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 0 | 0 |  |
Alabama Power |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 2,720 |  |  |
Total other comprehensive income (loss) | 2 | 2 | 4 |
Ending balance | 2,356 | 2,720 |  |
Regulatory asset | 70 | 76 | 97 |
Alabama Power | Pension plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 821 |  |  |
Ending balance | 741 | 821 |  |
Alabama Power | Pension plans | Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 821 | 679 |  |
Ending balance | 741 | 821 | 679 |
Alabama Power | Pension plans | Pension and Other Postretirement Benefit Plans | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | (17) | (11) |  |
Total other comprehensive income (loss) | (80) | 142 |  |
Alabama Power | Pension plans | Net loss | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | (63) | 153 |  |
Reclassification adjustments | (16) | (10) |  |
Alabama Power | Pension plans | Change in prior service costs | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | (1) | (1) |  |
Alabama Power | Pension plans | Amortization of regulatory assets | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 0 | 0 |  |
Alabama Power | Other Postretirement Benefits Plan |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 48 |  |  |
Ending balance | 45 | 48 |  |
Alabama Power | Other Postretirement Benefits Plan | Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | (48) | (21) |  |
Ending balance | (45) | (48) | (21) |
Alabama Power | Other Postretirement Benefits Plan | Pension and Other Postretirement Benefit Plans | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 2 | 3 |  |
Total other comprehensive income (loss) | 3 | (27) |  |
Alabama Power | Other Postretirement Benefits Plan | Net loss | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | (1) | 30 |  |
Reclassification adjustments | 3 | 3 |  |
Alabama Power | Other Postretirement Benefits Plan | Change in prior service costs | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | (1) | 0 |  |
Alabama Power | Other Postretirement Benefits Plan | Amortization of regulatory assets | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 0 | 0 |  |
Georgia Power |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 5,090 |  |  |
Total other comprehensive income (loss) | 22 | 3 | 28 |
Ending balance | 6,139 | 5,090 |  |
Regulatory asset |  |  | 83 |
Georgia Power | Pension plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 1,051 |  |  |
Ending balance | 973 | 1,051 |  |
Georgia Power | Pension plans | Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 1,051 | 887 |  |
Ending balance | 973 | 1,051 | 887 |
Georgia Power | Pension plans | Pension and Other Postretirement Benefit Plans | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | (20) | (14) |  |
Total other comprehensive income (loss) | (78) | 164 |  |
Georgia Power | Pension plans | Net loss | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | (58) | 178 |  |
Reclassification adjustments | (19) | (13) |  |
Georgia Power | Pension plans | Change in prior service costs | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | (1) | (1) |  |
Georgia Power | Pension plans | Amortization of regulatory assets | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 0 | 0 |  |
Georgia Power | Other Postretirement Benefits Plan |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 74 |  |  |
Ending balance | 64 | 74 |  |
Georgia Power | Other Postretirement Benefits Plan | Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | (74) | (39) |  |
Ending balance | (64) | (74) | (39) |
Georgia Power | Other Postretirement Benefits Plan | Pension and Other Postretirement Benefit Plans | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 4 | 3 |  |
Total other comprehensive income (loss) | 10 | (35) |  |
Georgia Power | Other Postretirement Benefits Plan | Net loss | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | (6) | 38 |  |
Reclassification adjustments | 5 | 4 |  |
Georgia Power | Other Postretirement Benefits Plan | Change in prior service costs | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | (1) | (1) |  |
Georgia Power | Other Postretirement Benefits Plan | Amortization of regulatory assets | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 0 | 0 |  |
Mississippi Power |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 90 |  |  |
Total other comprehensive income (loss) | 5 | 0 | 0 |
Ending balance | 59 | 90 |  |
Regulatory asset | 52 | 44 | 36 |
Mississippi Power | Pension plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 152 |  |  |
Ending balance | 144 | 152 |  |
Mississippi Power | Pension plans | Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 152 | 123 |  |
Ending balance | 144 | 152 | 123 |
Mississippi Power | Pension plans | Pension and Other Postretirement Benefit Plans | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | (3) | (2) |  |
Total other comprehensive income (loss) | (8) | 29 |  |
Mississippi Power | Pension plans | Net loss | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | (5) | 31 |  |
Reclassification adjustments | (3) | (2) |  |
Mississippi Power | Pension plans | Change in prior service costs | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 0 | 0 |  |
Mississippi Power | Pension plans | Amortization of regulatory assets | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 0 | 0 |  |
Mississippi Power | Other Postretirement Benefits Plan |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | (10) |  |  |
Ending balance | 9 | (10) |  |
Mississippi Power | Other Postretirement Benefits Plan | Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | (10) | (9) |  |
Ending balance | (9) | (10) | (9) |
Mississippi Power | Other Postretirement Benefits Plan | Pension and Other Postretirement Benefit Plans | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 0 | 0 |  |
Total other comprehensive income (loss) | 1 | (1) |  |
Mississippi Power | Other Postretirement Benefits Plan | Net loss | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | (1) | 1 |  |
Reclassification adjustments | 0 | 0 |  |
Mississippi Power | Other Postretirement Benefits Plan | Change in prior service costs | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 0 | 0 |  |
Mississippi Power | Other Postretirement Benefits Plan | Amortization of regulatory assets | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 0 | 0 |  |
Southern Company Gas |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | (2,225) |  |  |
Total other comprehensive income (loss) | 32 | (15) | 7 |
Ending balance | (2,252) | (2,225) |  |
Southern Company Gas | Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Total Stockholders' Equity (See accompanying statements) | 51 | 40 | 56 | 38
Total other comprehensive income (loss) | 11 | (16) | 18 |
Southern Company Gas | Pension plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 143 |  |  |
Ending balance | 126 | 143 |  |
Regulatory asset | 155 | 173 |  |
Southern Company Gas | Pension plans | Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 143 | 111 |  |
Total Stockholders' Equity (See accompanying statements) | (54) | (45) | (75) |
Reclassification adjustments | 2 | 1 |  |
Total other comprehensive income (loss) | (9) | 30 |  |
Ending balance | 126 | 143 | 111 |
Southern Company Gas | Pension plans | Pension and Other Postretirement Benefit Plans | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | (10) | (2) |  |
Total other comprehensive income (loss) | (17) | 32 |  |
Southern Company Gas | Pension plans | Net loss |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | (11) | 29 |  |
Reclassification adjustments | 0 | 0 |  |
Southern Company Gas | Pension plans | Net loss | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | (7) | 34 |  |
Reclassification adjustments | (1) | 0 |  |
Southern Company Gas | Pension plans | Change in prior service costs |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 2 | 1 |  |
Southern Company Gas | Pension plans | Change in prior service costs | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 2 | 2 |  |
Southern Company Gas | Pension plans | Amortization of regulatory assets | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | (11) | (4) |  |
Southern Company Gas | Other Postretirement Benefits Plan |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 68 |  |  |
Reclassification adjustments | 0 | (8) |  |
Ending balance | 84 | 68 |  |
Regulatory asset | 16 | 24 |  |
Southern Company Gas | Other Postretirement Benefits Plan | Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | (68) | (58) |  |
Total Stockholders' Equity (See accompanying statements) | (15) | (10) | (2) |
Total other comprehensive income (loss) | (5) | (8) |  |
Ending balance | (84) | (68) | (58) |
Southern Company Gas | Other Postretirement Benefits Plan | Pension and Other Postretirement Benefit Plans | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | (4) | (10) |  |
Total other comprehensive income (loss) | (16) | (10) |  |
Southern Company Gas | Other Postretirement Benefits Plan | Net loss |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | (5) | 0 |  |
Southern Company Gas | Other Postretirement Benefits Plan | Net loss | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | 12 | 0 |  |
Reclassification adjustments | 5 | 0 |  |
Southern Company Gas | Other Postretirement Benefits Plan | Change in prior service costs | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 0 | 0 |  |
Southern Company Gas | Other Postretirement Benefits Plan | Amortization of regulatory assets | Regulatory Assets |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | (9) | (10) |  |
SOUTHERN POWER CO |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Total Stockholders' Equity (See accompanying statements) | 6,682 | 6,698 | 6,916 | 6,598
Total other comprehensive income (loss) | 15 | 1 | 10 |
SOUTHERN POWER CO | Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Total Stockholders' Equity (See accompanying statements) | (9) | (16) | (9) | $ (29)
Total other comprehensive income (loss) | 7 | (7) | 20 |
SOUTHERN POWER CO | Pension plans | Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Total Stockholders' Equity (See accompanying statements) | 11 | 20 | 11 |
Reclassification adjustments | 0 | 0 |  |
Total other comprehensive income (loss) | (9) | 9 |  |
SOUTHERN POWER CO | Pension plans | Net loss |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | (9) | 9 |  |
Reclassification adjustments | 0 | 0 |  |
SOUTHERN POWER CO | Pension plans | Change in prior service costs |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 0 | 0 |  |
SOUTHERN POWER CO | Other Postretirement Benefits Plan |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Reclassification adjustments | 0 | 0 |  |
SOUTHERN POWER CO | Other Postretirement Benefits Plan | Pension and Other Postretirement Benefit Plans |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Total Stockholders' Equity (See accompanying statements) | 0 | 1 | $ 0 |
Total other comprehensive income (loss) | (1) | 1 |  |
SOUTHERN POWER CO | Other Postretirement Benefits Plan | Net loss |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |
Net gain (loss) | $ (1) | $ 1 |  |

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