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LEASES - Other Information (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Cash paid for amounts included in the measurements of lease obligations: |  |  |
Operating cash flows from operating leases | $ 253 | $ 303 | $ 308
Operating cash flows from finance leases | 15 | 11 | 9
Financing cash flows from finance leases | 18 | 16 | 17
ROU assets obtained under operating leases | 100 | 56 | 64
Reassessment of ROU assets under operating leases |  | 16 |
ROU assets obtained under finance leases | $ 3 | $ 118 | 3
Weighted-average remaining lease term in years: |  |  |
Operating leases | 17 years 2 months 12 days | 17 years 3 months 18 days |
Finance leases | 16 years 8 months 12 days | 17 years 4 months 24 days |
Weighted-average discount rate: |  |  |
Operating leases | 4.68% | 4.51% |
Finance leases | 4.85% | 4.87% |
Alabama Power |  |  |
Cash paid for amounts included in the measurements of lease obligations: |  |  |
Operating cash flows from operating leases | $ 17 | $ 58 | 58
Operating cash flows from finance leases | 0 | 0 | 0
Financing cash flows from finance leases | 2 | 1 | 1
ROU assets obtained under operating leases | 30 | 10 | 3
Reassessment of ROU assets under operating leases |  | 0 |
ROU assets obtained under finance leases | $ 3 | $ 2 | 0
Weighted-average remaining lease term in years: |  |  |
Operating leases | 11 years 1 month 6 days | 13 years |
Finance leases | 4 years 3 months 18 days | 6 years 4 months 24 days |
Weighted-average discount rate: |  |  |
Operating leases | 5.02% | 4.87% |
Finance leases | 3.93% | 3.00% |
Georgia Power |  |  |
Cash paid for amounts included in the measurements of lease obligations: |  |  |
Operating cash flows from operating leases | $ 199 | $ 206 | 211
Operating cash flows from finance leases | 22 | 20 | 17
Financing cash flows from finance leases | 16 | 10 | 9
ROU assets obtained under operating leases | 26 | 17 | 9
Reassessment of ROU assets under operating leases |  | 0 |
ROU assets obtained under finance leases | $ 18 | $ 116 | 0
Weighted-average remaining lease term in years: |  |  |
Operating leases | 7 years 6 months | 8 years 1 month 6 days |
Finance leases | 10 years 7 months 6 days | 11 years 9 months 18 days |
Weighted-average discount rate: |  |  |
Operating leases | 4.58% | 4.52% |
Finance leases | 5.95% | 8.06% |
Mississippi Power |  |  |
Cash paid for amounts included in the measurements of lease obligations: |  |  |
Operating cash flows from operating leases | $ 5 | $ 5 | 2
Operating cash flows from finance leases | 0 | 1 | 1
Financing cash flows from finance leases | 1 | 1 | 1
ROU assets obtained under operating leases | 1 | 9 | 0
Reassessment of ROU assets under operating leases |  | 0 |
ROU assets obtained under finance leases | $ 0 | $ 0 | 0
Weighted-average remaining lease term in years: |  |  |
Operating leases | 4 years 7 months 6 days | 4 years 8 months 12 days |
Finance leases | 11 years 10 months 24 days | 12 years 10 months 24 days |
Weighted-average discount rate: |  |  |
Operating leases | 3.67% | 3.49% |
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 | $ 30 | 28
Operating cash flows from finance leases | 0 | 0 | 0
Financing cash flows from finance leases | 0 | 0 | 0
ROU assets obtained under operating leases | 7 | 0 | 72
Reassessment of ROU assets under operating leases |  | 16 |
ROU assets obtained under finance leases | $ 0 | $ 0 | 0
Weighted-average remaining lease term in years: |  |  |
Operating leases | 33 years 1 month 6 days | 34 years |
Weighted-average discount rate: |  |  |
Operating leases | 4.89% | 4.86% |
Southern Company Gas |  |  |
Cash paid for amounts included in the measurements of lease obligations: |  |  |
Operating cash flows from operating leases | $ 12 | $ 14 | 19
Operating cash flows from finance leases | 0 | 0 | 0
Financing cash flows from finance leases | 0 | 0 | 0
ROU assets obtained under operating leases | 7 | 3 | 7
Reassessment of ROU assets under operating leases |  | 0 |
ROU assets obtained under finance leases | $ 0 | $ 0 | $ 0
Weighted-average remaining lease term in years: |  |  |
Operating leases | 7 years | 11 years |
Weighted-average discount rate: |  |  |
Operating leases | 3.80% | 3.79% |

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