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Investments, Loans and Long-Term Receivables - Dakota Access, LLC and Energy Transfer Crude Oil, Company, LLC (Details) $ in Millions		1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 01, 2024 USD ($)	Mar. 31, 2024 USD ($)	Sep. 30, 2025 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2025 USD ($) pipeline	Oct. 01, 2025	Dec. 31, 2024 USD ($)
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%
DAPL and ETCOP
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)	25.00%				25.00%
Repayments of debt		$ 250
Repayments of debt, contribution		$ 171
Repayments of debt, forgone distributions				$ 79
Maximum exposure, undiscounted					$ 215
Equity investments					$ 846		$ 883
WRB Refining LP
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)			50.00%		100.00%		50.00%
Equity investments			$ 1,300		$ 0		$ 2,323
Equity method investment impairment			$ 948
Dakota Access, LLC
Schedule of Equity Method Investments [Line Items]
Scheduled interest payments annually					$ 10
Phillips 66 Partners LP \| DAPL and ETCOP \| Variable Interest Entity, Primary Beneficiary
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)					25.00%
Number of pipelines \| pipeline					2
Senior Notes \| Dakota Access, LLC
Schedule of Equity Method Investments [Line Items]
Debt issued and guaranteed					$ 850
Dakota Senior Notes \| Senior Notes \| Dakota Access, LLC
Schedule of Equity Method Investments [Line Items]
Repayments of debt	$ 1,000