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Subsequent Event Subsequent Event (Details) - Mplx Lp [Member] - USD ($) $ in Millions | Jul. 21, 2017 | Oct. 27, 2015 | Nov. 20, 2014
--- | --- | --- | ---
Bank revolving credit facility due 2020 |  |  |
Subsequent Event [Line Items] |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  | $ 2,000 |
Debt Instrument, Term |  | 5 years |
MPLX bank revolving credit facility due July 2022 [Member] | Subsequent Event [Member] |  |  |
Subsequent Event [Line Items] |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | $ 2,250 |  |
Debt Instrument, Term | 5 years |  |
Term loan facility due 2019 |  |  |
Subsequent Event [Line Items] |  |  |
Line of Credit Facility, Current Borrowing Capacity |  |  | $ 250

X
- Definition Period of time between issuance and maturity of debt instrument, 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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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. + References No definition available. + 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
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