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Master Limited Partnership - Dropdowns to MPLX and GP/IDR Exchange (Details) - MPLX shares in Millions, $ in Billions | Feb. 01, 2018 USD ($) shares
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MPLX 364-day term loan |
Noncontrolling Interest [Line Items] |
Maximum borrowing capacity | $ | $ 4.1
Debt instrument, term | 364 days
Cash and Cash Equivalents |
Noncontrolling Interest [Line Items] |
Cash consideration | $ | $ 4.1
Limited Partner |
Noncontrolling Interest [Line Items] |
Units issued, number of units | 112
Conversion of stock, units issued | 275
General Partner |
Noncontrolling Interest [Line Items] |
Units issued, number of units | 2

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