Ownership Interest In Assets Sold By Company In Affiliate

No definition available.

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- Definition

Proceeds From Sale Of Ownership Interest In Assets Sold By Company In Affiliate

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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Balance Type:	credit
Period Type:	instant

- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

+ Details

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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

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of units or percentage investment held in the subsidiary by the limited liability company or limited partnership.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611443-123010

+ Details

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Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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MPLX LP (Dropdowns to MPLX) (Details) - USD ($) shares in Thousands, $ in Millions						12 Months Ended
	Sep. 01, 2016	Mar. 31, 2016	Dec. 04, 2015	Dec. 01, 2014	Mar. 01, 2014	Dec. 31, 2016
MPLX LP \| Limited Partner
Noncontrolling Interest [Line Items]
Units issued, number of units	7,000	23,000		2,900
Equity interest issued, value assigned		$ 600		$ 200
MPLX LP \| General Partner
Noncontrolling Interest [Line Items]
Units issued, number of units		460
MPLX LP \| MPLX Revolver
Noncontrolling Interest [Line Items]
Cash payment for acquisition				$ 600	$ 270
MPLX LP \| Cash and cash equivalents
Noncontrolling Interest [Line Items]
Cash payment for acquisition					$ 40
MPLX Pipe Line Holdings LP
Noncontrolling Interest [Line Items]
Additional interest sold			0.50%	30.50%	13.00%
Proceeds from sale of ownership interest in assets sold by company in affiliate			$ 12	$ 600	$ 310
MPLX Pipe Line Holdings LP \| MPLX LP
Noncontrolling Interest [Line Items]
Ownership interest (in percentage)			100.00%			100.00%