Guarantees.

No definition available.

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- Definition

Percentage of guarantee.

+ References

No definition available.

+ Details

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Namespace Prefix:	psx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Terms Of Guarantees Outstanding

+ References

No definition available.

+ Details

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 25
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Term of the lessee's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Details

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- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_IndemnificationGuaranteeMember
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Data Type:	na
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- Details

Name:	us-gaap_BalanceSheetLocationAxis=psx_AssetRetirementObligationsAndAccruedEnvironmentalCostMember
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=psx_ResidualValueGuaranteesMember
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- Details

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Guarantees (Narrative) (Details) - USD ($) $ in Millions	6 Months Ended
Guarantees (Narrative) (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015	Dec. 31, 2012
Guarantees (Textual) [Abstract]
Environmental accruals included in recorded carrying amount	$ 486	$ 485
Other Guarantees [Member]
Guarantees (Textual) [Abstract]
Maximum potential amount of future payments under the guarantees	112
Indemnifications [Member]
Guarantees (Textual) [Abstract]
Carrying amount of indemnifications	193
Asset Retirement Obligations And Accrued Environmental Cost [Member] \| Indemnifications [Member]
Guarantees (Textual) [Abstract]
Environmental accruals included in recorded carrying amount	$ 98
Maximum [Member] \| Other Guarantees [Member]
Guarantees (Textual) [Abstract]
Term of the guarantees, in years	8 years
Merey Sweeny [Member]
Guarantees (Textual) [Abstract]
Maximum potential amount of future payments under the guarantees	$ 179
Merey Sweeny [Member] \| MSLP 8.85% Senior Notes [Member] \| Guarantees of Joint Venture Debt [Member]
Guarantees (Textual) [Abstract]
Percentage of guarantee			100.00%
Maximum potential amount of future payments under the guarantees	140
Facilities [Member] \| Residual Value Guarantees [Member]
Guarantees (Textual) [Abstract]
Maximum potential amount of future payments under the guarantees	$ 554
Facilities [Member] \| Maximum [Member] \| Other Guarantees [Member]
Guarantees (Textual) [Abstract]
Lessee leasing arrangements, operating leases, term of contract	5 years
Railcar and Airplane [Member] \| Residual Value Guarantees [Member]
Guarantees (Textual) [Abstract]
Maximum potential amount of future payments under the guarantees	$ 376