This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Investments, Loans and Long-Term Receivables - Liberty Pipeline LLC (Liberty) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Impairment charges		$ 60	$ 1,498	$ 4,252
Equity investments		$ 14,414	$ 12,832
Liberty Pipeline, LLC \| Variable Interest Entity, Primary Beneficiary \| Phillips 66 Partners LP
Schedule of Equity Method Investments [Line Items]
Impairment charges	$ 198
Equity investments	$ 46