Balance Sheet Components (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Accounts Receivable, Allowance for Credit Loss	$ 11		$ 11		$ 11	$ 9
Unbilled Receivables, Current	137		137			138
Finite-Lived Intangible Assets, Accumulated Amortization	595		595			558
Line of Credit Facility, Maximum Borrowing Capacity	$ 850		$ 850
Debt Instrument, Covenant Description			65.00%
Ratio of Indebtedness to Net Capital	0.567		0.567
Line of Credit Facility, Remaining Borrowing Capacity	$ 750		$ 750
Line of Credit Facility, Current Borrowing Capacity	750		750
Authorized Short-Term Debt	900		900
Purchased power and fuel	275	$ 220	680	$ 524
Repayments of Long-term Debt			0	260
Amount above baseline net variable power costs			52
Revenues	758	648	1,687	1,396
Letters of Credit Outstanding, Amount	86		86
Line of Credit, Current	320		320
Finance Lease, Liability, to be Paid	737		737
Revenues	758	$ 648	1,687	$ 1,396
Regulatory assets - noncurrent	617		617			492
Regulatory liabilities-noncurrent	1,406		1,406			1,398
Fire
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Regulatory assets - noncurrent	21		21			23
wildfire
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Regulatory assets - noncurrent	21		21			$ 10
Letter of Credit [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Commercial paper	$ 0		$ 0