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CONSOLIDATED ENTITIES AND EQUITY METHOD INVESTMENTS - SPC Noncontrolling Interests and VIEs Narrative (Details) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 USD ($) investor | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Redeemable Noncontrolling Interest [Line Items] |  |  |
Total assets | $ 139,331 | $ 134,891 | $ 127,534
Liabilities | 104,106 | 100,359 |
Equity investments in unconsolidated subsidiaries | 1,368 | 1,443 |
Southern Power |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |
Total assets | 12,761 | 13,081 |
Liabilities | 6,063 | 6,165 |
Proceeds from sale of equity method investments | 50 | 38 |
Equity investments in unconsolidated subsidiaries | $ 0 | 49 |
Southern Power | SP Solar Holdings I, LP |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |
Sale of equity interest in limited partnership | 33.00% |  |
Wholly Owned Subsidiary Of Southern Power | Southern Power | SP Solar Holdings I, LP |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |
Ownership interest | 66.00% |  |
Wholly Owned Subsidiary Of Southern Power | Southern Power | SP Wind |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |
Ownership interest | 100.00% |  |
SP Solar Holdings I, LP | Southern Power |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |
Distribution made to limited partner, cash distributions paid, percentage | 67.00% |  |
SP Solar Holdings I, LP | Global Atlantic |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |
Distribution made to limited partner, cash distributions paid, percentage | 33.00% |  |
SP Wind | Southern Power |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |
Distribution made to limited partner, cash distributions paid, percentage | 60.00% |  |
Number of financial investors | investor | 3 |  |
SP Wind | Financial Investors |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |
Distribution made to limited partner, cash distributions paid, percentage | 40.00% |  |
General Partner | Wholly Owned Subsidiary Of Southern Power | Southern Power | SP Solar Holdings I, LP |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |
Ownership interest | 1.00% |  |
Variable Interest Entity, Primary Beneficiary | SP Solar Holdings I, LP | Southern Power |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |
Total assets | $ 5,600 | 5,900 |
Liabilities | 400 |  |
Noncontrolling interests related to other partners' interest | 1,000 | 1,100 |
Variable Interest Entity, Primary Beneficiary | SP Wind | Southern Power |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |
Total assets | 2,100 | 2,200 |
Liabilities | 187 | 169 |
Noncontrolling interests related to other partners' interest | 38 | 39 |
Variable Interest Entity, Primary Beneficiary | Other Variable Interest Entities | Southern Power |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |
Total assets | 1,700 | $ 1,800 |
Liabilities | 200 |  |
Noncontrolling interests related to other partners' interest | $ 800 |  |

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