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LEASES - Undiscounted Cash Flows to be Received Under PPAs Accounted for as Operating Leases (Details) $ in Millions | Dec. 31, 2023 USD ($)
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Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract] |
2024 | $ 116
2025 | 107
2026 | 108
2027 | 105
2028 | 104
Thereafter | 706
Total | 1,246
Alabama Power |
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract] |
2024 | 7
2025 | 5
2026 | 5
2027 | 4
2028 | 3
Thereafter | 26
Total | 50
Southern Power |
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract] |
2024 | 90
2025 | 75
2026 | 73
2027 | 75
2028 | 76
Thereafter | 91
Total | 480
Southern Company Gas |
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract] |
2024 | 35
2025 | 29
2026 | 29
2027 | 28
2028 | 28
Thereafter | 354
Total | $ 503

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