v3.26.1
Financing and Leases - DOE Loan Guarantee Borrowings (Details) - USD ($)
$ in Millions
1 Months Ended 6 Months Ended
Feb. 20, 2026
Mar. 31, 2026
Jun. 30, 2026
Line of Credit Facility [Line Items]      
Line of credit facility, maximum borrowing capacity     $ 8,920
GEORGIA POWER CO      
Line of Credit Facility [Line Items]      
Line of credit facility, maximum borrowing capacity     $ 2,050
GEORGIA POWER CO | FFB Credit Facility      
Line of Credit Facility [Line Items]      
Borrower reimbursement, maximum percentage of eligible project costs 80.00%    
Line of credit facility, maximum borrowing capacity $ 22,400    
Interest rate   5.041%  
Debt Instrument, Basis Spread on Variable Rate     0.375%
Prepayment requirement, percentage of total advances made to borrower, minimum threshold 95.00%    
Mandatory prepayment, percentage of principal to be prepaid 100.00%    
Proceeds from Lines of Credit   $ 1,000  
GEORGIA POWER CO | FFB Credit Facility | Minimum      
Line of Credit Facility [Line Items]      
Mandatory prepayment, payable period 1 year    
GEORGIA POWER CO | FFB Credit Facility | Maximum      
Line of Credit Facility [Line Items]      
Mandatory prepayment, payable period 5 years    
ALABAMA POWER CO      
Line of Credit Facility [Line Items]      
Line of credit facility, maximum borrowing capacity     $ 1,365
ALABAMA POWER CO | FFB Credit Facility      
Line of Credit Facility [Line Items]      
Borrower reimbursement, maximum percentage of eligible project costs 80.00%    
Line of credit facility, maximum borrowing capacity $ 4,100    
Debt Instrument, Basis Spread on Variable Rate     0.375%
Prepayment requirement, percentage of total advances made to borrower, minimum threshold 95.00%    
Mandatory prepayment, percentage of principal to be prepaid 100.00%    
ALABAMA POWER CO | FFB Credit Facility | Minimum      
Line of Credit Facility [Line Items]      
Mandatory prepayment, payable period 1 year    
ALABAMA POWER CO | FFB Credit Facility | Maximum      
Line of Credit Facility [Line Items]      
Mandatory prepayment, payable period 3 years