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Pay vs Performance Disclosure | 5 Months Ended | 7 Months Ended | 12 Months Ended
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May 24, 2023 | Dec. 31, 2023 | Dec. 31, 2024 USD ($) percentile | Dec. 31, 2023 USD ($) percentile | Dec. 31, 2022 USD ($) percentile | Dec. 31, 2021 USD ($) percentile | Dec. 31, 2020 USD ($) percentile
Pay vs Performance Disclosure |  |  |  |  |  |  |
Pay vs Performance Disclosure, Table |  |  |
| PEO Pay |  | Non-PEO Pay |  | Value of Initial Fixed $100 Investment Based On |  | Percentile
Fiscal Year (a) | Summary Compensation Table Total for CEO ($) (b) | Compensation Actually Paid to CEO ($) (c) |  | Average Summary Compensation Table Total for non-CEO NEOs ($) (d) | Average Compensation Actually Paid to non-CEO NEOs ($) (e) |  | Southern Total Shareholder Return ($) (f) | Peer Group Total Shareholder Return ($) (g) | Net Income ($ millions) (h) | Company Selected Measure One-Year Relative TSR (percentile) (i)
| Womack | Fanning | Womack | Fanning |  |  |  |  |  |  |  |
2024 | 23,885,173 |  | — |  | 28,200,592 |  | — |  |  | 5,207,018 |  | 7,724,411 |  |  | 157.57 |  | 122.12 |  | 4,401 |  | 68th
2023 | 23,521,052 |  | 33,469,800 |  | 18,378,941 |  | 40,567,478 |  |  | 5,555,346 |  | 6,433,480 |  |  | 129.49 |  | 101.02 |  | 3,976 |  | 86th
2022 |  | 24,006,670 |  |  | 42,131,615 |  |  | 5,668,554 |  | 6,722,302 |  |  | 126.71 |  | 111.24 |  | 3,524 |  | 77th
2021 |  | 21,243,559 |  |  | 35,516,807 |  |  | 5,210,958 |  | 7,015,374 |  |  | 117.07 |  | 113.92 |  | 2,393 |  | 45th
2020 |  | 22,366,850 |  |  | 23,821,625 |  |  | 7,160,434 |  | 6,386,601 |  |  | 100.63 |  | 99.38 |  | 3,119 |  | 70th
Named Executive Officers, Footnote |  |  | 2024: CEO - Christopher C. Womack; Other NEOs - Daniel S. Tucker, Stanley W. Connally, Jr., Kimberly S. Greene and James Y. Kerr 2023: CEO - Thomas A. Fanning: January 1 to May 24, Christopher C. Womack: May 24 to December 31; Other NEOs - Daniel S. Tucker, Kimberly S. Greene, James Y. Kerr and Stephen E. Kuczynski 2022: CEO - Thomas A. Fanning; Other NEOs - Daniel S. Tucker, Christopher C. Womack, Stephen E. Kuczynski and Mark A. Crosswhite 2021: CEO - Thomas A. Fanning; Other NEOs - Daniel S. Tucker, Mark. A. Crosswhite, Stephen E. Kuczynski, Christopher C. Womack, Andrew W. Evans and W. Paul Bowers 2020: CEO - Thomas A. Fanning; Other NEOs - Andrew W. Evans, W. Paul Bowers, Mark A. Crosswhite and Stephen E. Kuczynski |  |  |  |
Peer Group Issuers, Footnote |  |  | The peer group utilized in the table above is the Philadelphia Utilities Sector Index (UTY). For each Covered Year, the peer group cumulative TSR was calculated based on a deemed fixed investment of $100 in the index through each Measurement Period, assuming dividend reinvestment. |  |  |  |
PEO Total Compensation Amount |  |  | $ 23,885,173 |  |  |  |
PEO Actually Paid Compensation Amount |  |  | $ 28,200,592 |  |  |  |
Adjustment To PEO Compensation, Footnote |  |  | To calculate Compensation Actually Paid (CAP) to the CEO for 2024, the following amounts were deducted from and added to the “Total” compensation amount for the CEO reflected in each year’s Summary Compensation Table (SCT):
2024 Fiscal Year | Summary Compensation Total ($) | Minus: SCT “Stock Awards” ($) | Minus: SCT “Change in Pension Value and Nonqualified Deferred Compensation” ($) | Add: Stock Award Fair Value ($) | Add: Pension Service Costs ($) | Compensation Actually Paid ($)
PEO | 23,885,173 |  | 11,725,994 |  | 7,142,735 |  | 22,427,771 |  | 756,377 |  | 28,200,592 |
Average Non-PEO NEOs | 5,207,018 |  | 2,436,842 |  | 515,338 |  | 5,096,980 |  | 372,593 |  | 7,724,411 |
The deductions of “Stock Awards” and “Change in Pension Value and Nonqualified Deferred Compensation” are found in columns (d) and (f) of the SCT for each covered year. Stock Award Fair Value The addition of Stock Award Fair Value reflects:
| PEO | Average Non-PEO NEOs
Fair Value of Awards Granted during Year that remain unvested as of Year-End |  | $ | 18,037,633 |  |  | $ | 3,667,445 |
Fair Value of Awards Granted during Year that vested during such Year |  | — |  |  | — |
Change in Fair Value from prior December 31 to December 31 of Year of Awards Granted in Prior Years that remain outstanding and unvested |  | $ | 3,873,645 |  |  | $ | 1,023,690 |
Change in Fair Value from Prior December 31 to Vesting Date for Awards that vested during Year |  | $ | 516,493 |  |  | $ | 405,845 |
Deduction of Fair Value of Awards Granted in Prior Years that were forfeited during Year |  | — |  |  | — |
Increase based upon Incremental Fair Value of Awards modified during Year |  | — |  |  | — |
Increase based on Dividends or Other Earnings Paid during Year prior to Vesting Date of Award |  | — |  |  | — |
Total |  | $ | 22,427,771 |  |  | $ | 5,096,980 |
Stock Award Fair Value was calculated based on the probable outcome of performance conditions as of the relevant measurement date, consistent with the approach described on page 64. Pension Service Cost The addition of Pension Service Costs reflects the annual service costs for the Pension Plan and supplemental pension plans described on page 69. 4 Womack: Pension Plan - $48,854; SBP-P and SERP - $707,523 4 Average Non-PEO NEOs: Pension Plan - $47,085; SBP-P and SERP - $325,509 There were no plan amendments during the covered year that resulted in prior service costs. |  |  |  |
Non-PEO NEO Average Total Compensation Amount |  |  | $ 5,207,018 | $ 5,555,346 | $ 5,668,554 | $ 5,210,958 | $ 7,160,434
Non-PEO NEO Average Compensation Actually Paid Amount |  |  | $ 7,724,411 | 6,433,480 | 6,722,302 | 7,015,374 | 6,386,601
Adjustment to Non-PEO NEO Compensation Footnote |  |  | To calculate Compensation Actually Paid (CAP) to the CEO for 2024, the following amounts were deducted from and added to the “Total” compensation amount for the CEO reflected in each year’s Summary Compensation Table (SCT):
2024 Fiscal Year | Summary Compensation Total ($) | Minus: SCT “Stock Awards” ($) | Minus: SCT “Change in Pension Value and Nonqualified Deferred Compensation” ($) | Add: Stock Award Fair Value ($) | Add: Pension Service Costs ($) | Compensation Actually Paid ($)
PEO | 23,885,173 |  | 11,725,994 |  | 7,142,735 |  | 22,427,771 |  | 756,377 |  | 28,200,592 |
Average Non-PEO NEOs | 5,207,018 |  | 2,436,842 |  | 515,338 |  | 5,096,980 |  | 372,593 |  | 7,724,411 |
The deductions of “Stock Awards” and “Change in Pension Value and Nonqualified Deferred Compensation” are found in columns (d) and (f) of the SCT for each covered year. Stock Award Fair Value The addition of Stock Award Fair Value reflects:
| PEO | Average Non-PEO NEOs
Fair Value of Awards Granted during Year that remain unvested as of Year-End |  | $ | 18,037,633 |  |  | $ | 3,667,445 |
Fair Value of Awards Granted during Year that vested during such Year |  | — |  |  | — |
Change in Fair Value from prior December 31 to December 31 of Year of Awards Granted in Prior Years that remain outstanding and unvested |  | $ | 3,873,645 |  |  | $ | 1,023,690 |
Change in Fair Value from Prior December 31 to Vesting Date for Awards that vested during Year |  | $ | 516,493 |  |  | $ | 405,845 |
Deduction of Fair Value of Awards Granted in Prior Years that were forfeited during Year |  | — |  |  | — |
Increase based upon Incremental Fair Value of Awards modified during Year |  | — |  |  | — |
Increase based on Dividends or Other Earnings Paid during Year prior to Vesting Date of Award |  | — |  |  | — |
Total |  | $ | 22,427,771 |  |  | $ | 5,096,980 |
Stock Award Fair Value was calculated based on the probable outcome of performance conditions as of the relevant measurement date, consistent with the approach described on page 64. Pension Service Cost The addition of Pension Service Costs reflects the annual service costs for the Pension Plan and supplemental pension plans described on page 69. 4 Womack: Pension Plan - $48,854; SBP-P and SERP - $707,523 4 Average Non-PEO NEOs: Pension Plan - $47,085; SBP-P and SERP - $325,509 There were no plan amendments during the covered year that resulted in prior service costs. |  |  |  |
Compensation Actually Paid vs. Total Shareholder Return |  |  | Compensation Actually Paid v. Southern TSR & Peer Group TSR |  |  |  |
Compensation Actually Paid vs. Net Income |  |  |
Compensation Actually Paid vs. Net Income | Compensation Actually Paid vs. 1-Yr rTSR*
* As noted above, our 2024 LTI program utilized and applied significant weighting to our 3-year relative TSR metric, rather than the 1-year relative TSR metric shown. For more information, see page 54. |  |  |  |
Compensation Actually Paid vs. Company Selected Measure |  |  |
Compensation Actually Paid vs. Net Income | Compensation Actually Paid vs. 1-Yr rTSR*
* As noted above, our 2024 LTI program utilized and applied significant weighting to our 3-year relative TSR metric, rather than the 1-year relative TSR metric shown. For more information, see page 54. |  |  |  |
Total Shareholder Return Vs Peer Group |  |  | Compensation Actually Paid v. Southern TSR & Peer Group TSR |  |  |  |
Tabular List, Table |  |  |
1-year Relative TSR
3-year Relative TSR
Return on Equity (ROE)
Earnings per Share (EPS)
GHG Reduction Metric
Total Shareholder Return Amount |  |  | $ 157.57 | 129.49 | 126.71 | 117.07 | 100.63
Peer Group Total Shareholder Return Amount |  |  | 122.12 | 101.02 | 111.24 | 113.92 | 99.38
Net Income (Loss) |  |  | $ 4,401,000,000 | $ 3,976,000,000 | $ 3,524,000,000 | $ 2,393,000,000 | $ 3,119,000,000
Company Selected Measure Amount | percentile |  |  | 68 | 86 | 77 | 45 | 70
PEO Name | Thomas A. Fanning | Christopher C. Womack | Christopher C. Womack |  | Thomas A. Fanning | Thomas A. Fanning | Thomas A. Fanning
Additional 402(v) Disclosure |  |  | Descriptions of Relationships Between CAP and Certain Financial Performance Measure Results The following charts provide, across the Covered Years, a clear description of the relationships between (1) our cumulative TSR and the cumulative TSR for the peer group reflected in the PVP Table above, (2) PEO CAP and the financial performance measures results set forth in columns (f), (h) and (i) of the PVP Table above and (3) non-PEO NEO CAP and the financial performance measures results set forth in columns (f), (h) and (i) of the PVP Table above. |  |  |  |
Measure:: 1 |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Name |  |  | 1-year Relative TSR |  |  |  |
Non-GAAP Measure Description |  |  | For each Covered Year, our absolute TSR was calculated based on the yearly percentage change in our cumulative TSR on our common stock, par value $5.00 per share, measured as the quotient of (a) the sum of (i) the cumulative amount of dividends for the period beginning with our closing stock price on the NYSE on December 31, 2019 through and including the last day of the covered year (each, a Measurement Period), assuming dividend reinvestment, plus (ii) the difference between our closing stock price at the end versus the beginning of the Measurement Period, divided by (b) our closing share price at the beginning of the Measurement Period. Each of these yearly percentage changes was then applied to a deemed fixed investment of $100 at the beginning of each Measurement Period to produce the Covered Year-end values of such investment as of the end of the Covered Year, as applicable. Because Covered Years are presented in the table in reverse chronological order (from top to bottom), the table should be read from bottom to top for purposes of understanding cumulative returns over time. For purposes of this PvP disclosure, our relative TSR is calculated substantially as described above in our Compensation Discussion and Analysis. See page 54 for more information on the calculation of relative TSR and the results shown in this Pay Versus Performance disclosure. |  |  |  |
Measure:: 2 |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Name |  |  | 3-year Relative TSR |  |  |  |
Measure:: 3 |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Name |  |  | Return on Equity (ROE) |  |  |  |
Measure:: 4 |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Name |  |  | Earnings per Share (EPS) |  |  |  |
Measure:: 5 |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Name |  |  | GHG Reduction Metric |  |  |  |
Womack [Member] |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
PEO Total Compensation Amount |  |  | $ 23,885,173 | $ 23,521,052 |  |  |
PEO Actually Paid Compensation Amount |  |  | 28,200,592 | 18,378,941 |  |  |
Fanning [Member] |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
PEO Total Compensation Amount |  |  | 0 | 33,469,800 | $ 24,006,670 | $ 21,243,559 | $ 22,366,850
PEO Actually Paid Compensation Amount |  |  | 0 | $ 40,567,478 | $ 42,131,615 | $ 35,516,807 | $ 23,821,625
PEO | Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | (7,142,735) |  |  |  |
PEO | Aggregate Pension Adjustments Service Cost |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 756,377 |  |  |  |
PEO | Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | (11,725,994) |  |  |  |
PEO | Equity Awards Adjustments, Excluding Value Reported in Compensation Table |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 22,427,771 |  |  |  |
PEO | Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 18,037,633 |  |  |  |
PEO | Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 3,873,645 |  |  |  |
PEO | Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 0 |  |  |  |
PEO | Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 516,493 |  |  |  |
PEO | Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 0 |  |  |  |
PEO | Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 0 |  |  |  |
PEO | Chain In Fair Value Based Upon Awards Modified During Year [Member] |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 0 |  |  |  |
Non-PEO NEO | Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | (515,338) |  |  |  |
Non-PEO NEO | Aggregate Pension Adjustments Service Cost |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 372,593 |  |  |  |
Non-PEO NEO | Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | (2,436,842) |  |  |  |
Non-PEO NEO | Equity Awards Adjustments, Excluding Value Reported in Compensation Table |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 5,096,980 |  |  |  |
Non-PEO NEO | Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 3,667,445 |  |  |  |
Non-PEO NEO | Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 1,023,690 |  |  |  |
Non-PEO NEO | Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 0 |  |  |  |
Non-PEO NEO | Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 405,845 |  |  |  |
Non-PEO NEO | Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 0 |  |  |  |
Non-PEO NEO | Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | 0 |  |  |  |
Non-PEO NEO | Chain In Fair Value Based Upon Awards Modified During Year [Member] |  |  |  |  |  |  |
Pay vs Performance Disclosure |  |  |  |  |  |  |
Adjustment to Compensation, Amount |  |  | $ 0 |  |  |  |

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