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Investments, Loans and Long-Term Receivables - Schedule of Affiliated Companies Accounted for Equity Method (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 01, 2025	Oct. 01, 2025	Sep. 30, 2025	Jan. 30, 2025	Dec. 31, 2024
Schedule of Equity Method Investments [Line Items]
Equity investments	$ 11,425					$ 14,013
WRB Refining LP
Schedule of Equity Method Investments [Line Items]
Ownership interest acquired (as a percent)			50.00%	50.00%
Retail Marketing Business \| Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Retail Marketing Business
Schedule of Equity Method Investments [Line Items]
Ownership percentage, divested		65.00%
Chevron Phillips Chemical Company LLC
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)	50.00%
Equity investments	$ 7,899					$ 7,819
WRB Refining LP
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)	100.00%			50.00%		50.00%
Equity investments	$ 0			$ 1,300		$ 2,323
Gulf Coast Express Pipeline LLC
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)	0.00%				25.00%
Equity investments	$ 0					776
Dakota Access, LLC
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)	25.00%
Equity investments	$ 748					777
JET Management Holding
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)	35.00%	35.00%
Equity investments	$ 743					0
Front Range Pipeline LLC
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)	33.33%
Equity investments	$ 436					459
CF United LLC
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)	47.09%
Equity investments	$ 298					284
OnCue Holdings LLC
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)	50.00%
Equity investments	$ 211					$ 185
Maximum loss exposure	265
Maximum exposure of loss/potential amount of future payments	$ 54