Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

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

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-Topic 835
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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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.

+ References

No definition available.

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- Definition

Fair value of the amount outstanding under the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Debt (Details) - USD ($)	1 Months Ended
Debt (Details) - USD ($)	Mar. 31, 2018	Mar. 31, 2019	Mar. 22, 2019	Dec. 31, 2018	Mar. 01, 2018
Debt Instrument [Line Items]
Long-term debt		$ 11,268,000,000		$ 11,093,000,000
Senior Notes
Debt Instrument [Line Items]
Debt issued and guaranteed					$ 1,500,000,000
Senior Notes \| Floating Rate Notes Due 2021
Debt Instrument [Line Items]
Debt issued and guaranteed					500,000,000
Senior Notes \| Senior Notes Due 2028
Debt Instrument [Line Items]
Debt issued and guaranteed					$ 800,000,000
Stated interest rate of debt issued, percentage					3.90%
Senior Notes \| Senior Notes Due 2044
Debt Instrument [Line Items]
Debt issued and guaranteed					$ 200,000,000
Stated interest rate of debt issued, percentage					4.875%
London Interbank Offered Rate (LIBOR) \| Senior Notes \| Floating Rate Notes Due 2021
Debt Instrument [Line Items]
Basis spread on variable rate	0.60%
Variable Interest Entity, Primary Beneficiary \| Phillips 66 Partners LP
Debt Instrument [Line Items]
Long-term debt		550,000,000
Variable Interest Entity, Primary Beneficiary \| Phillips 66 Partners LP \| Term Loan Due 2020
Debt Instrument [Line Items]
Line of credit Facility, maximum borrowing capacity			$ 400,000,000
Variable Interest Entity, Primary Beneficiary \| Phillips 66 Partners LP \| Loans Payable \| Term Loan Due 2020
Debt Instrument [Line Items]
Debt issued and guaranteed		250,000,000
Revolving Credit Facility \| Variable Interest Entity, Primary Beneficiary \| Phillips 66 Partners LP
Debt Instrument [Line Items]
Line of credit Facility, maximum borrowing capacity		750,000,000
Line of credit facility, amount outstanding		$ 15,000,000		$ 125,000,000