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LEASES - Balance Sheet Amounts Recorded for Operating and Financing Leases (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Operating Leases |  |
Operating lease ROU assets, net | $ 1,386 | $ 1,432
Operating lease obligations - current | 200 | 183
Operating lease obligations - non-current | 1,253 | 1,307
Total operating lease obligations | $ 1,453 | $ 1,490
Finance Leases |  |
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] | Public Utilities, Other Depreciable Property, Plant And Equipment, Plant In Service | Public Utilities, Other Depreciable Property, Plant And Equipment, Plant In Service
Finance lease ROU assets, net | $ 254 | $ 272
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] | Other Liabilities, Current | Other Liabilities, Current
Finance lease obligations - current | $ 9 | $ 11
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] | Long-Term Debt | Long-Term Debt
Finance lease obligations - non-current | $ 278 | $ 287
Total finance lease obligations | 287 | 298
Assets Subject to Power Purchase Agreement |  |
Operating Leases |  |
Total operating lease obligations | 567 | 566
Alabama Power |  |
Operating Leases |  |
Operating lease ROU assets, net | $ 84 | $ 87
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] | Other Liabilities, Current | Other Liabilities, Current
Operating lease obligations - current | $ 14 | $ 12
Operating lease obligations - non-current | 76 | 81
Total operating lease obligations | $ 90 | $ 93
Finance Leases |  |
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] | Public Utilities, Other Depreciable Property, Plant And Equipment, Plant In Service | Public Utilities, Other Depreciable Property, Plant And Equipment, Plant In Service
Finance lease ROU assets, net | $ 4 | $ 5
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] | Other Liabilities, Current | Other Liabilities, Current
Finance lease obligations - current | $ 1 | $ 2
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] | Long-Term Debt | Long-Term Debt
Finance lease obligations - non-current | $ 3 | $ 3
Total finance lease obligations | 4 | 5
Alabama Power | Assets Subject to Power Purchase Agreement |  |
Operating Leases |  |
Total operating lease obligations | 55 | 58
Georgia Power |  |
Operating Leases |  |
Operating lease ROU assets, net | 1,331 | 884
Operating lease obligations - current | 169 | 135
Operating lease obligations - non-current | 1,159 | 740
Total operating lease obligations | $ 1,328 | $ 875
Finance Leases |  |
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] | Public Utilities, Other Depreciable Property, Plant And Equipment, Plant In Service | Public Utilities, Other Depreciable Property, Plant And Equipment, Plant In Service
Finance lease ROU assets, net | $ 227 | $ 203
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] | Other Liabilities, Current | Other Liabilities, Current
Finance lease obligations - current | $ 20 | $ 18
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] | Long-Term Debt | Long-Term Debt
Finance lease obligations - non-current | $ 241 | $ 222
Total finance lease obligations | 261 | 240
Georgia Power | Assets Subject to Power Purchase Agreement |  |
Operating Leases |  |
Total operating lease obligations | $ 1,300 | $ 813
Mississippi Power |  |
Operating Leases |  |
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] | Other deferred charges and assets | Other deferred charges and assets
Operating lease ROU assets, net | $ 8 | $ 9
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] | Other Liabilities, Current | Other Liabilities, Current
Operating lease obligations - current | $ 4 | $ 3
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] | Other Liabilities, Noncurrent | Other Liabilities, Noncurrent
Operating lease obligations - non-current | $ 4 | $ 6
Total operating lease obligations | $ 8 | $ 9
Finance Leases |  |
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] | Public Utilities, Other Depreciable Property, Plant And Equipment, Plant In Service | Public Utilities, Other Depreciable Property, Plant And Equipment, Plant In Service
Finance lease ROU assets, net | $ 14 | $ 15
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] | Other Liabilities, Current | Other Liabilities, Current
Finance lease obligations - current | $ 1 | $ 1
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] | Long-Term Debt | Long-Term Debt
Finance lease obligations - non-current | $ 13 | $ 15
Total finance lease obligations | 14 | 16
Southern Power |  |
Operating Leases |  |
Operating lease ROU assets, net | $ 484 | $ 488
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] | Other Liabilities, Current | Other Liabilities, Current
Operating lease obligations - current | $ 29 | $ 29
Operating lease obligations - non-current | 511 | 517
Total operating lease obligations | 540 | 546
Finance Leases |  |
Finance lease ROU assets, net | 0 | 0
Finance lease obligations - current | 0 | 0
Finance lease obligations - non-current | 0 | 0
Total finance lease obligations | 0 | 0
Southern Company Gas |  |
Operating Leases |  |
Operating lease ROU assets, net | $ 38 | $ 47
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] | Other Liabilities, Current | Other Liabilities, Current
Operating lease obligations - current | $ 11 | $ 11
Operating lease obligations - non-current | 30 | 40
Total operating lease obligations | 41 | 51
Finance Leases |  |
Finance lease ROU assets, net | 0 | 0
Finance lease obligations - current | 0 | 0
Finance lease obligations - non-current | 0 | 0
Total finance lease obligations | $ 0 | $ 0

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