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Related Party Agreements and Transactions - Employee Services Agreements (Detail) - MPC - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017
Related Party Transaction [Line Items] |  |
Expenses incurred under employee services agreements | $ 138 | $ 117
Rental cost of sales - related parties |  |
Related Party Transaction [Line Items] |  |
Expenses incurred under employee services agreements | 1 | 0
Purchases - related parties |  |
Related Party Transaction [Line Items] |  |
Expenses incurred under employee services agreements | 114 | 92
General and administrative expenses |  |
Related Party Transaction [Line Items] |  |
Expenses incurred under employee services agreements | $ 23 | $ 25

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- Definition The aggregate amount of expenditures for salaries, wages, profit sharing and incentive compensation, and other employee benefits, including equity-based compensation, and pension and other postretirement benefit expense. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.4) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + 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. + Details
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- Details
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- Details
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