Regulatory Matters - Regulatory Assets (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Regulatory Assets [Line Items]
Total regulatory assets	$ 5,349	$ 5,565
Regulatory assets, current	1,136	1,398
Regulatory assets, noncurrent	4,213	4,167
Regulatory assets not earning a return on investment	$ 2,100	3,200
Deferred net power costs
Regulatory Assets [Line Items]
Regulatory asset, amortization period	1 year
Total regulatory assets	$ 1,400	1,769
Asset retirement obligations
Regulatory Assets [Line Items]
Regulatory asset, amortization period	19 years
Total regulatory assets	$ 1,031	930
Deferred income taxes
Regulatory Assets [Line Items]
Total regulatory assets	$ 455	435
Employee benefit plans
Regulatory Assets [Line Items]
Regulatory asset, amortization period	13 years
Total regulatory assets	$ 386	414
Demand side management
Regulatory Assets [Line Items]
Regulatory asset, amortization period	9 years
Total regulatory assets	$ 281	245
Wildfire mitigation and vegetation management costs
Regulatory Assets [Line Items]
Total regulatory assets	$ 208	114
Levelized depreciation
Regulatory Assets [Line Items]
Regulatory asset, amortization period	28 years
Total regulatory assets	$ 185	167
Unrealized losses on regulated derivative contracts
Regulatory Assets [Line Items]
Regulatory asset, amortization period	1 year
Total regulatory assets	$ 182	173
Environmental costs
Regulatory Assets [Line Items]
Regulatory asset, amortization period	29 years
Total regulatory assets	$ 145	139
Asset disposition costs
Regulatory Assets [Line Items]
Total regulatory assets	$ 140	135
Cost of removal
Regulatory Assets [Line Items]
Regulatory asset, amortization period	26 years
Total regulatory assets	$ 122	143
Other
Regulatory Assets [Line Items]
Total regulatory assets	$ 814	$ 901