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Debt - MPLX Senior Notes (Details) - MPLX LP $ in Millions | Feb. 08, 2018 USD ($)
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MPLX 364-day term loan |
Debt Instrument [Line Items] |
Repayments of short-term debt | $ 4,100
Senior Notes |
Debt Instrument [Line Items] |
Long-term debt, gross | 5,500
Senior Notes | MPLX senior notes, 3.375%, due March 2023 |
Debt Instrument [Line Items] |
Long-term debt, gross | $ 500
Debt instrument, interest rate | 3.375%
Senior Notes | MPLX senior notes, 4.000%, due March 2028 |
Debt Instrument [Line Items] |
Long-term debt, gross | $ 1,250
Debt instrument, interest rate | 4.00%
Senior Notes | MPLX senior notes, 4.500%, due April 2038 |
Debt Instrument [Line Items] |
Long-term debt, gross | $ 1,750
Debt instrument, interest rate | 4.50%
Senior Notes | MPLX senior notes, 4.700%, due April 2048 |
Debt Instrument [Line Items] |
Long-term debt, gross | $ 1,500
Debt instrument, interest rate | 4.70%
Senior Notes | MPLX senior notes, 4.900%, due April 2058 |
Debt Instrument [Line Items] |
Long-term debt, gross | $ 500
Debt instrument, interest rate | 4.90%

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + 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 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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