Derivatives and Risk Management - Schedules of Fair Values and Locations of Derivative Instruments (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Derivatives, Fair Value [Line Items]
Gross Asset	$ 17	$ 24
Gross Liability	(52)	(64)
Collateral Netted	6	24
Net Asset (Liability) on Balance Sheet	(29)	(16)
Other Current Liabilities [Member] \| Commodity Contracts [Member]
Derivatives, Fair Value [Line Items]
Gross Asset	6	11
Gross Liability	(36)	(48)
Collateral Netted	5	23
Net Asset (Liability) on Balance Sheet	(25)	(14)
Other Current Assets [Member] \| Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Gross Asset		1
Net Asset (Liability) on Balance Sheet		1
Other Current Assets [Member] \| Commodity Contracts [Member]
Derivatives, Fair Value [Line Items]
Gross Asset	5	10
Gross Liability	0
Collateral Netted	0
Net Asset (Liability) on Balance Sheet	5	10
Other Property and Investments-Net and Other Non-current Assets [Member] \| Commodity Contracts [Member]
Derivatives, Fair Value [Line Items]
Gross Asset	2
Gross Liability	0
Collateral Netted	0
Net Asset (Liability) on Balance Sheet	2
Other Noncurrent Liabilities [Member] \| Commodity Contracts [Member]
Derivatives, Fair Value [Line Items]
Gross Asset	4	2
Gross Liability	(16)	(16)
Collateral Netted	1	1
Net Asset (Liability) on Balance Sheet	$ (11)	$ (13)

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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