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LEASES - Undiscounted Cash Flows to be Received Under PPAs Accounted for as Operating Leases (Details) $ in Millions | Dec. 31, 2021 USD ($)
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Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract] |
2022 | $ 188
2023 | 139
2024 | 107
2025 | 100
2026 | 99
Thereafter | 883
Total | 1,516
Alabama Power |
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract] |
2022 | 76
2023 | 32
2024 | 5
2025 | 3
2026 | 3
Thereafter | 23
Total | 142
Georgia Power |
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract] |
2022 | 8
2023 | 2
2024 | 0
2025 | 0
2026 | 0
Thereafter | 0
Total | 10
Southern Power |
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract] |
2022 | 87
2023 | 88
2024 | 90
2025 | 74
2026 | 73
Thereafter | 240
Total | 652
Southern Company Gas |
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract] |
2022 | 35
2023 | 35
2024 | 33
2025 | 28
2026 | 28
Thereafter | 407
Total | $ 566

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