Commitments and Contingencies, Asset Retirement Obligations (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2024		Dec. 31, 2023
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance		$ 22	[1]	$ 28
Accretion		1
Cash Flow Revisions	[2]			(7)
Ending balance	[1]	23		22
Steam, hydro and other production
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance		9		10
Accretion		1		0
Cash Flow Revisions	[2]			(1)
Ending balance		10		9
Electric Plant Electric Distribution
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance		5		5
Accretion		0		0
Cash Flow Revisions	[2]			0
Ending balance		5		5
Natural Gas Plant Gas Distribution
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance		8		13
Accretion		0		1
Cash Flow Revisions	[2]			(6)
Ending balance		$ 8		$ 8

[1] Included in other long-term liabilities balance in the consolidated balance sheet.

[2] In 2023, AROs were revised for changes in timing and estimates of cash flows. Changes in gas distribution AROs were a result of updated mileage of gas lines and number of services, as well as changes to inflation and discount rate assumptions.