Balance Sheet Components Regulatory Assets and Liabilities (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets, Current	$ 13		$ 13		$ 24
Regulatory assets - noncurrent	506		506		533
Regulatory Liability, Current	160		160		106
Regulatory liabilities-noncurrent	1,402		1,402		1,360
Purchased power and fuel	337	$ 259	707	$ 613
Increase (Decrease) in Accounts Payable and Other Operating Liabilities	30		30
Removal Costs [Member]
Regulatory Assets and Liabilities [Line Items]
Regulatory Liability, Current	0		0		0
Regulatory liabilities-noncurrent	1,130		1,130		1,047
Deferred Income Tax Charge [Member]
Regulatory Assets and Liabilities [Line Items]
Regulatory Liability, Current	0		0		0
Regulatory liabilities-noncurrent	198		198		208
Asset Retirement Obligation Costs [Member]
Regulatory Assets and Liabilities [Line Items]
Regulatory Liability, Current	0		0		0
Regulatory liabilities-noncurrent	6		6		43
Revenue Subject to Refund [Member]
Regulatory Assets and Liabilities [Line Items]
Regulatory liabilities-noncurrent	12		12		0
Other Regulatory Assets (Liabilities) [Member]
Regulatory Assets and Liabilities [Line Items]
Regulatory Liability, Current	28		28		51
Regulatory liabilities-noncurrent	56		56		62
Regulatory Clause Revenues, under-recovered
Regulatory Assets and Liabilities [Line Items]
Regulatory Liability, Current	132		132		55
Deferred Derivative Gain (Loss) [Member]
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets, Current	0		0		0
Regulatory assets - noncurrent	0		0		55
Pension and Other Postretirement Plans Costs [Member]
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets, Current	0		0		0
Regulatory assets - noncurrent	121		121		131
Loss on Reacquired Debt [Member]
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets, Current	0		0		0
Regulatory assets - noncurrent	22		22		23
Environmental Restoration Costs [Member]
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets, Current	0		0		0
Regulatory assets - noncurrent	101		101		90
Other Regulatory Assets (Liabilities) [Member]
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets, Current	13		13		24
Regulatory assets - noncurrent	69		69		57
Storm Costs
Regulatory Assets and Liabilities [Line Items]
Increase (Decrease) in Accounts Payable and Other Operating Liabilities	73		73		67
221119 Other Electric Power Generation
Regulatory Assets and Liabilities [Line Items]
Increase (Decrease) in Accounts Payable and Other Operating Liabilities	30		30		29
Fire
Regulatory Assets and Liabilities [Line Items]
Increase (Decrease) in Accounts Payable and Other Operating Liabilities	31		31		45
pandemic
Regulatory Assets and Liabilities [Line Items]
Increase (Decrease) in Accounts Payable and Other Operating Liabilities	34		34		$ 36
wildfire
Regulatory Assets and Liabilities [Line Items]
Increase (Decrease) in Accounts Payable and Other Operating Liabilities	$ 25		$ 25