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v3.23.2

Consolidated Entities and Equity Method Investments - Narrative (Details) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Mar. 31, 2023 USD ($) | Jun. 30, 2023 USD ($) investor | Dec. 31, 2022 USD ($)
Schedule of Equity Method Investments [Line Items] |  |  |
Equity investments in unconsolidated subsidiaries |  | $ 1,382 | $ 1,443
Assets |  | 137,116 | 134,891
Liabilities |  | 102,468 | 100,359
Southern Holdings Company |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Equity investments in unconsolidated subsidiaries |  | 122 | 112
SOUTHERN POWER CO |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Equity investments in unconsolidated subsidiaries |  | 0 | 49
Assets |  |  | 13,081
Liabilities |  | $ 6,199 | 6,165
Proceeds from sale of equity method investments | $ 50 |  |
SP Solar Holdings I, LP | SOUTHERN POWER CO |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Distribution made to limited partner, cash distributions paid, percentage |  | 67.00% |
SP Solar Holdings I, LP | Global Atlantic |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Distribution made to limited partner, cash distributions paid, percentage |  | 33.00% |
Variable Interest Entity, Primary Beneficiary | SP Solar Holdings I, LP | SOUTHERN POWER CO |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Assets |  | $ 5,800 | 5,900
Liabilities |  | 400 |
Noncontrolling interests related to other partners' interests |  | 1,000 | 1,100
Variable Interest Entity, Primary Beneficiary | SP Wind | SOUTHERN POWER CO |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Assets |  | 2,200 |
Liabilities |  | 175 | 169
Noncontrolling interests related to other partners' interests |  | $ 39 |
Distribution made to limited partner, cash distributions paid, percentage |  | 60.00% |
Number of financial investors | investor |  | 3 |
Variable Interest Entity, Primary Beneficiary | SP Wind | Financial Investors |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Distribution made to limited partner, cash distributions paid, percentage |  | 40.00% |
Variable Interest Entity, Primary Beneficiary | Other Variable Interest Entities | SOUTHERN POWER CO |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Assets |  | $ 1,700 | $ 1,800
Liabilities |  | 200 |
Noncontrolling interests related to other partners' interests |  | $ 800 |

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