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LEASES - Other Information (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Cash paid for amounts included in the measurements of lease obligations: |  |  |
Operating cash flows from operating leases | $ 243 | $ 253 | $ 303
Operating cash flows from finance leases | 15 | 15 | 11
Financing cash flows from finance leases | 11 | 18 | 16
ROU assets obtained under operating leases | 146 | 100 | 56
Reassessment of ROU assets under operating leases | (7) |  | 16
ROU assets obtained under finance leases | $ 1 | $ 3 | 118
Weighted-average remaining lease term in years: |  |  |
Operating leases | 16 years 4 months 24 days | 17 years 2 months 12 days |
Finance leases | 16 years | 16 years 8 months 12 days |
Weighted-average discount rate: |  |  |
Operating leases | 4.73% | 4.68% |
Finance leases | 4.86% | 4.85% |
Alabama Power |  |  |
Cash paid for amounts included in the measurements of lease obligations: |  |  |
Operating cash flows from operating leases | $ 19 | $ 17 | 58
Operating cash flows from finance leases | 0 | 0 | 0
Financing cash flows from finance leases | 2 | 2 | 1
ROU assets obtained under operating leases | 11 | 30 | 10
Reassessment of ROU assets under operating leases | 0 |  | 0
ROU assets obtained under finance leases | $ 0 | $ 3 | 2
Weighted-average remaining lease term in years: |  |  |
Operating leases | 10 years 2 months 12 days | 11 years 1 month 6 days |
Finance leases | 2 years 8 months 12 days | 4 years 3 months 18 days |
Weighted-average discount rate: |  |  |
Operating leases | 5.04% | 5.02% |
Finance leases | 4.05% | 3.93% |
Georgia Power |  |  |
Cash paid for amounts included in the measurements of lease obligations: |  |  |
Operating cash flows from operating leases | $ 186 | $ 199 | 206
Operating cash flows from finance leases | 21 | 22 | 20
Financing cash flows from finance leases | 23 | 16 | 10
ROU assets obtained under operating leases | 609 | 26 | 17
Reassessment of ROU assets under operating leases | 0 |  | 0
ROU assets obtained under finance leases | $ 44 | $ 18 | 116
Weighted-average remaining lease term in years: |  |  |
Operating leases | 7 years 10 months 24 days | 7 years 6 months |
Finance leases | 10 years 1 month 6 days | 10 years 7 months 6 days |
Weighted-average discount rate: |  |  |
Operating leases | 4.73% | 4.58% |
Finance leases | 5.80% | 5.95% |
Mississippi Power |  |  |
Cash paid for amounts included in the measurements of lease obligations: |  |  |
Operating cash flows from operating leases | $ 4 | $ 5 | 5
Operating cash flows from finance leases | 0 | 0 | 1
Financing cash flows from finance leases | 1 | 1 | 1
ROU assets obtained under operating leases | 0 | 1 | 9
Reassessment of ROU assets under operating leases | 0 |  | 0
ROU assets obtained under finance leases | $ 0 | $ 0 | 0
Weighted-average remaining lease term in years: |  |  |
Operating leases | 4 years 3 months 18 days | 4 years 7 months 6 days |
Finance leases | 10 years 10 months 24 days | 11 years 10 months 24 days |
Weighted-average discount rate: |  |  |
Operating leases | 3.83% | 3.67% |
Finance leases | 2.74% | 2.74% |
Southern Power |  |  |
Cash paid for amounts included in the measurements of lease obligations: |  |  |
Operating cash flows from operating leases | $ 33 | $ 33 | 30
Operating cash flows from finance leases | 0 | 0 | 0
Financing cash flows from finance leases | 0 | 0 | 0
ROU assets obtained under operating leases | 10 | 7 | 0
Reassessment of ROU assets under operating leases | (7) |  | 16
ROU assets obtained under finance leases | $ 0 | $ 0 | 0
Weighted-average remaining lease term in years: |  |  |
Operating leases | 32 years 3 months 18 days | 33 years 1 month 6 days |
Weighted-average discount rate: |  |  |
Operating leases | 4.88% | 4.89% |
Southern Company Gas |  |  |
Cash paid for amounts included in the measurements of lease obligations: |  |  |
Operating cash flows from operating leases | $ 12 | $ 12 | 14
Operating cash flows from finance leases | 0 | 0 | 0
Financing cash flows from finance leases | 0 | 0 | 0
ROU assets obtained under operating leases | 1 | 7 | 3
Reassessment of ROU assets under operating leases | 0 |  | 0
ROU assets obtained under finance leases | $ 0 | $ 0 | $ 0
Weighted-average remaining lease term in years: |  |  |
Operating leases | 6 years 9 months 18 days | 7 years |
Weighted-average discount rate: |  |  |
Operating leases | 3.84% | 3.80% |

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