v3.25.2
Selected Balance Sheet Data - Inventories (Details) - USD ($)
$ in Millions
Jun. 30, 2025
Dec. 31, 2024
Inventory [Line Items]    
Total Inventories $ 29 $ 28
Materials and supplies    
Inventory [Line Items]    
Inventories 15 13
Fuel    
Inventory [Line Items]    
Inventories 11 10
Natural gas    
Inventory [Line Items]    
Inventories $ 3 $ 5