v3.25.0.1
PROPERTY, PLANT, AND EQUIPMENT - Deferred Cloud Implementation Costs (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Property, Plant and Equipment [Line Items]      
Total deferred charges and other assets $ 19,599 $ 19,069  
Deferred Cloud Implementation Costs      
Property, Plant and Equipment [Line Items]      
Total deferred charges and other assets 321 325  
Amortization 56 46 $ 29
Alabama Power      
Property, Plant and Equipment [Line Items]      
Total deferred charges and other assets 5,175 5,090  
Alabama Power | Deferred Cloud Implementation Costs      
Property, Plant and Equipment [Line Items]      
Total deferred charges and other assets 92 85  
Amortization 17 11 8
Georgia Power      
Property, Plant and Equipment [Line Items]      
Total deferred charges and other assets 11,142 10,200  
Georgia Power | Deferred Cloud Implementation Costs      
Property, Plant and Equipment [Line Items]      
Total deferred charges and other assets 111 99  
Amortization 22 19 12
Mississippi Power      
Property, Plant and Equipment [Line Items]      
Total deferred charges and other assets 841 887  
Mississippi Power | Deferred Cloud Implementation Costs      
Property, Plant and Equipment [Line Items]      
Total deferred charges and other assets 13 13  
Amortization 0 0 0
Southern Power      
Property, Plant and Equipment [Line Items]      
Total deferred charges and other assets 950 998  
Southern Power | Deferred Cloud Implementation Costs      
Property, Plant and Equipment [Line Items]      
Total deferred charges and other assets 12 15  
Amortization 0 0 $ 0
Southern Company Gas      
Property, Plant and Equipment [Line Items]      
Total deferred charges and other assets 902 890  
Southern Company Gas | Deferred Cloud Implementation Costs      
Property, Plant and Equipment [Line Items]      
Total deferred charges and other assets $ 35 $ 43