Number of non-employee directors

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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

Net number of non-option equity instruments granted to participants.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Unit-Based Compensation (Details)	12 Months Ended
Unit-Based Compensation (Details)	Dec. 31, 2019 director shares	Dec. 31, 2018 shares	Dec. 31, 2017 shares	Dec. 31, 2013 shares
Phantom Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of non-employee directors \| director	3
Phillips 66 Partners LP 2013 Incentive Compensation Plan \| Phantom Units \| Non Employee Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of phantom units granted (in shares)	4,950	4,326	4,794
Phillips 66 Partners LP 2013 Incentive Compensation Plan \| Common Units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common units that may be delivered under the ICP Plan (in shares)				2,500,000