v3.25.2
Other Comprehensive Income (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]        
Accumulated other comprehensive loss at beginning of period     $ 10,735  
Accumulated other comprehensive loss at end of period $ 11,660   11,660  
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent        
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]        
Accumulated other comprehensive loss at beginning of period (18) $ (19) (18) $ (19)
Net current period other comprehensive loss 1 1 1 1
Accumulated other comprehensive loss at end of period (17) (18) (17) (18)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Interest Rate Swap        
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]        
Losses reclassified from net accumulated other comprehensive loss (1) [1] (1) [1] (1) [2] (1) [2]
Defined Benefit and Postretirement Items        
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]        
Accumulated other comprehensive loss at beginning of period (1) (1) (1) (1)
Net current period other comprehensive loss 0 0 0 0
Accumulated other comprehensive loss at end of period (1) (1) (1) (1)
Defined Benefit and Postretirement Items | Interest Rate Swap        
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]        
Losses reclassified from net accumulated other comprehensive loss 0 [1] 0 [1] 0 [2] 0 [2]
Total        
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]        
Accumulated other comprehensive loss at beginning of period (19) (20) (19) (20)
Net current period other comprehensive loss 1 1 1 1
Accumulated other comprehensive loss at end of period (18) (19) (18) (19)
Total | Interest Rate Swap        
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]        
Losses reclassified from net accumulated other comprehensive loss $ (1) [1] $ (1) [1] $ (1) [2] $ (1) [2]
[1] Included in interest charges.
[2] Included in interest charges