Employee Benefits Plans (Details Textual 1) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Stock Option [Member]
Employee Benefit Plans Additional (Textual) [Abstract]
Vest ratably options term, in year	10 years
Portion of options or units that are vesting	33.00%
Vesting period of stock options or stock units	6 months
Weighted-average remaining contractual term of outstanding options	5 years 8 months 2 days
Weighted-average remaining contractual term exercisable	4 years 4 months 5 days
Weighted-Average Grant-Date Fair Value, granted	$ 5.39	$ 9.54	$ 10.17
Aggregate Intrinsic Value, exercised	$ 0	$ 10	$ 89
Cash received from exercise of stock options	3
Tax benefit from exercise of options	4
Unrecognized compensation cost from stock options	$ 8
Weighted average period of recognition of unvested options, in months	10 months 20 days
Longest weighted-average period of recognition of unvested options, in months	2 years 1 month 17 days
Stock Options Vested [Member]
Employee Benefit Plans Additional (Textual) [Abstract]
Weighted-average remaining contractual term of outstanding options	5 years 3 months 7 days
Stock Unit Program [Member]
Employee Benefit Plans Additional (Textual) [Abstract]
Vest ratably options term, in year	3 years
Weighted-Average Grant-Date Fair Value, granted		$ 65.4	$ 62.72
Unrecognized compensation cost from stock options	$ 105
Weighted average period of recognition of unvested options, in months	1 year 7 months 11 days
Longest weighted-average period of recognition of unvested options, in months	2 years 9 months 1 day
Total Fair Value, Issued	$ 191	$ 316	$ 256
Performance Share Program [Member]
Employee Benefit Plans Additional (Textual) [Abstract]
Vest ratably options term, in year	3 years
Phillips 66 [Member]
Employee Benefit Plans Additional (Textual) [Abstract]
Unrecognized compensation cost from stock options	$ 1
Stock Settled Performance Share Program [Member]
Employee Benefit Plans Additional (Textual) [Abstract]
Weighted-Average Grant-Date Fair Value, granted		$ 69.25	$ 65.46
Years of service required for award	5 years
Retirement eligible age	55
Unrecognized compensation cost from stock options	$ 3
Weighted average period of recognition of unvested options, in months	1 year 9 months 4 days
Longest weighted-average period of recognition of unvested options, in months	3 years 11 months 27 days
Total Fair Value, Issued	$ 17	$ 25	$ 18
Cash Settled Performance Share Program [Member]
Employee Benefit Plans Additional (Textual) [Abstract]
Weighted-Average Grant-Date Fair Value, granted		$ 46.54	$ 69.23
Years of service required for award	5 years
PSU termination date	Dec. 31, 2016	Dec. 31, 2015
Unrecognized compensation cost from stock options	$ 7
Weighted average period of recognition of unvested options, in months	1 year 9 months 6 days
Longest weighted-average period of recognition of unvested options, in months	3 years 1 month 17 days
Total Fair Value, Issued	$ 31	$ 6	$ 0
Other [Member]
Employee Benefit Plans Additional (Textual) [Abstract]
Weighted-Average Grant-Date Fair Value, granted		$ 58.66	$ 71.23
Total Fair Value, Issued		$ 3	$ 3

Employee benefit plans.

No definition available.

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- Definition

Employee service share based compensation unrecognized compensation costs on nonvested award longest weighted average period of recognition.

+ References

No definition available.

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- Definition

Options awarded vesting and exercisable on each anniversary date following the date of grant.

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- Definition

Vest ratably options term in year.

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No definition available.

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- Definition

Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

Date the equity-based award expires, in CCYY-MM-DD format.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Weighted average remaining contractual term for fully vested and expected to vest options that are exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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