Summary of Significant Accounting Policies (Details) $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Depreciation expense expressed as a percentage of average depreciable property	3.40%	3.20%	3.10%
Cash and Cash Equivalents [Abstract]
Maximum number of months remaing	3 months
Accounts and Financing Receivable, after Allowance for Credit Loss, Current and Noncurrent [Abstract]
Accounts Receivable, Allowance for Credit Loss, Current	$ 54	$ 40
Alternative Revenue Programs [Abstract]
Number of DSM Products, Commercial and Industrial Customers	20
Number of DSM Products, Residential and Low-income Customers	23
maximum number of months following end of annual period in which revenues are to be included	24 months
DSM Measurements	1,000
Public Utilities, Inventory [Line Items]
Inventories	$ 319	245
Maximum number of months remaing	3 months
maximum number of months following end of annual period in which revenues are to be included	24 months
Materials and supplies
Public Utilities, Inventory [Line Items]
Inventories	$ 80	70
Public Utilities, Inventory, Fuel [Member]
Public Utilities, Inventory [Line Items]
Inventories	68	71
Public Utilities, Inventory, Natural Gas [Member]
Public Utilities, Inventory [Line Items]
Inventories	$ 171	$ 104