v3.25.0.1
LEASES - Lease Income (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Lessor, Lease, Description [Line Items]      
Lease income - interest income on sales-type leases $ 24 $ 24 $ 25
Lease income - operating leases 136 164 208
Variable lease income 417 406 417
Total lease income $ 577 $ 594 $ 650
Operating lease, income, comprehensive income, extensible list, not disclosed, flag Lease income - operating leases Lease income - operating leases Lease income - operating leases
Alabama Power      
Lessor, Lease, Description [Line Items]      
Lease income - interest income on sales-type leases $ 0 $ 0 $ 0
Lease income - operating leases 9 35 77
Variable lease income 1 1 1
Total lease income 10 36 78
Georgia Power      
Lessor, Lease, Description [Line Items]      
Lease income - interest income on sales-type leases 0 0 0
Lease income - operating leases 28 29 32
Variable lease income 0 0 0
Total lease income 28 29 32
Mississippi Power      
Lessor, Lease, Description [Line Items]      
Lease income - interest income on sales-type leases 15 14 15
Lease income - operating leases 3 2 2
Variable lease income 0 0 0
Total lease income 18 16 17
Southern Power      
Lessor, Lease, Description [Line Items]      
Lease income - interest income on sales-type leases 9 10 10
Lease income - operating leases 88 85 85
Variable lease income 450 437 448
Total lease income 547 532 543
Southern Company Gas      
Lessor, Lease, Description [Line Items]      
Lease income - interest income on sales-type leases 0 0 0
Lease income - operating leases 36 37 36
Variable lease income 0 0 0
Total lease income $ 36 $ 37 $ 36