Debt Instrument, Redemption, Principal Intended To Be Redeemed

No definition available.

Name:	psx_DebtInstrumentRedemptionPrincipalIntendedToBeRedeemed
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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

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Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	instant

- Definition

Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase.

+ References

No definition available.

+ Details

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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- Definition

Amount of cash outflow for short-term and long-term debt. Excludes payment of lease obligation.

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Debt - Issuances and Repayments (Details) - USD ($) $ in Millions										12 Months Ended
	Dec. 04, 2025	Feb. 18, 2025	Dec. 16, 2024	Mar. 29, 2024	Mar. 04, 2024	Feb. 15, 2024	May 19, 2023	Mar. 29, 2023	Mar. 15, 2023	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Jun. 27, 2025	Sep. 20, 2024	Sep. 11, 2024	Feb. 28, 2024
Debt Instrument [Line Items]
Issuance of debt										$ 8,395	$ 6,272	$ 6,260
Loss (gain) on early redemption of debt										$ 0	$ (3)	$ 53
Senior Notes Due December 2031, 2035 And 2055 \| Senior Notes
Debt Instrument [Line Items]
Debt issued and guaranteed															$ 1,800
5.250% Senior Notes Due 2031 \| Senior Notes
Debt Instrument [Line Items]
Debt issued and guaranteed															$ 600	$ 600
Debt interest rate (as a percent)															5.25%	5.25%
4.950% Senior Notes Due 2035 \| Senior Notes
Debt Instrument [Line Items]
Debt issued and guaranteed															$ 600
Debt interest rate (as a percent)															4.95%
5.500% Senior Notes Due 2055 \| Senior Notes
Debt Instrument [Line Items]
Debt issued and guaranteed															$ 600
Debt interest rate (as a percent)															5.50%
Senior Notes Due December 2031, 2033 And 2054 \| Senior Notes
Debt Instrument [Line Items]
Debt issued and guaranteed																$ 1,500
5.300% Senior Notes Due 2033 \| Senior Notes
Debt Instrument [Line Items]
Debt issued and guaranteed																$ 400
Debt interest rate (as a percent)																5.30%
5.650% Senior Notes Due 2054 \| Senior Notes
Debt Instrument [Line Items]
Debt issued and guaranteed																$ 500
Debt interest rate (as a percent)																5.65%
Senior Notes Due 2027 And 2033 \| Senior Notes
Debt Instrument [Line Items]
Debt issued and guaranteed								$ 1,250
4.950% Senior Notes due December 2027 \| Senior Notes
Debt Instrument [Line Items]
Debt interest rate (as a percent)								4.95%		4.95%	4.95%
Issuance of debt								$ 750
Debt										$ 750	$ 750
4.950% Senior Notes due December 2027 \| Senior Notes \| DCP Midstream, LP
Debt Instrument [Line Items]
Debt										$ 0	$ 0
5.300% Senior Notes due June 2033 \| Senior Notes
Debt Instrument [Line Items]
Debt interest rate (as a percent)								5.30%		5.30%	5.30%
Issuance of debt								$ 500
Debt										$ 900	$ 900
5.300% Senior Notes due June 2033 \| Senior Notes \| DCP Midstream, LP
Debt Instrument [Line Items]
Debt										0	$ 0
1.300% Senior Notes due February 2026 \| Senior Notes
Debt Instrument [Line Items]
Debt issued and guaranteed										$ 100
Debt interest rate (as a percent)										1.30%	1.30%
Debt instrument, repurchased face amount										$ 400
Debt										100	$ 500
1.300% Senior Notes due February 2026 \| Senior Notes \| DCP Midstream, LP
Debt Instrument [Line Items]
Debt										0	$ 0
5.375% Senior Notes due July 2025 \| Senior Notes
Debt Instrument [Line Items]
Debt issued and guaranteed													$ 825
Debt interest rate (as a percent)											5.375%		5.375%
Debt instrument, repurchased face amount													$ 525
Debt											$ 525
5.375% Senior Notes due July 2025 \| Senior Notes \| DCP Midstream, LP
Debt Instrument [Line Items]
Debt											525
3.605% Senior Notes Due February 2025 \| Senior Notes
Debt Instrument [Line Items]
Debt interest rate (as a percent)		3.605%												3.605%
Repayments of debt		$ 59
2.450% Senior Notes due December 2024 \| Senior Notes
Debt Instrument [Line Items]
Debt interest rate (as a percent)			2.45%
Repayments of debt			$ 300
Junior Subordinated Notes due 2025 \| Senior Notes \| DCP Midstream, LP
Debt Instrument [Line Items]
Debt interest rate (as a percent)				5.375%
Repayments of debt				$ 825
Aggregate principal amount intended to be redeemed				$ 300
Term Loan Agreement
Debt Instrument [Line Items]
Repayments of debt	$ 550
Term Loan Agreement \| Line of Credit \| Secured Debt
Debt Instrument [Line Items]
Repayments of debt					$ 700
Debt					$ 1,250					$ 0	$ 550
0.900% Senior Notes due February 2024 \| Senior Notes
Debt Instrument [Line Items]
Debt interest rate (as a percent)						0.90%
Repayments of debt						$ 800
5.850% Junior Subordinated Notes due May 2043 \| Junior Subordinated Notes \| DCP Midstream, LP
Debt Instrument [Line Items]
Debt interest rate (as a percent)							5.85%
Aggregate principal amount intended to be redeemed							$ 550
Debt							497
Loss (gain) on early redemption of debt							$ 53
3.875% Senior Notes due March 2023 \| Senior Notes \| DCP Midstream, LP
Debt Instrument [Line Items]
Debt interest rate (as a percent)									3.875%
Repayments of debt									$ 500