Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Depreciation expense expressed as a percentage of average depreciable property	3.90%	3.40%	3.40%
Accounts and Financing Receivable, after Allowance for Credit Loss, Current and Noncurrent [Abstract]
Accounts Receivable, Allowance for Credit Loss, Current	$ 12	$ 15
Alternative Revenue Programs [Abstract]
maximum number of months following end of annual period	24 months
Public Utilities, Inventory [Line Items]
Inventory	$ 71	$ 69
maximum number of months following end of annual period	24 months
Depreciation expense expressed as a percentage of average depreciable property	3.90%	3.40%	3.40%
Supplies
Public Utilities, Inventory [Line Items]
Inventory	$ 60	$ 56
Fuel
Public Utilities, Inventory [Line Items]
Inventory	$ 11	$ 13