Balance Sheet Components (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Accounts Receivable, Allowance for Credit Loss	$ 11		$ 9
Unbilled Receivables, Current	132		138
Finite-Lived Intangible Assets, Accumulated Amortization	576		558
Line of Credit Facility, Maximum Borrowing Capacity	$ 850
Debt Instrument, Covenant Description	65.00%
Ratio of Indebtedness to Net Capital	0.569
Line of Credit Facility, Remaining Borrowing Capacity	$ 750
Line of Credit Facility, Current Borrowing Capacity	750
Authorized Short-Term Debt	900
Purchased power and fuel	405	$ 304
Repayments of Long-term Debt	0	260
Amount above baseline net variable power costs	(19)
Revenues	929	748
Letters of Credit Outstanding, Amount	131
Line of Credit, Current	320
Finance Lease, Liability, to be Paid	737
Revenues	929	$ 748
Regulatory assets - noncurrent	606		492
Regulatory liabilities-noncurrent	1,406		1,398
Fire
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Regulatory assets - noncurrent	22		23
wildfire
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Regulatory assets - noncurrent	13		$ 10
Letter of Credit [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Commercial paper	$ 0