Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Depreciation expense expressed as a percentage of average depreciable property	3.40%	3.30%	3.10%
Accounts and Financing Receivable, after Allowance for Credit Loss, Current and Noncurrent [Abstract]
Accounts Receivable, Allowance for Credit Loss, Current	$ 13	$ 12
Alternative Revenue Programs [Abstract]
maximum number of months following end of annual period	24 months
Public Utilities, Inventory [Line Items]
Inventory	$ 61	51
maximum number of months following end of annual period	24 months
Maturity period	3 months
Supplies
Public Utilities, Inventory [Line Items]
Inventory	$ 42	29
Fuel
Public Utilities, Inventory [Line Items]
Inventory	$ 19	$ 22