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Acquisitions and Investments - Investment in Pipeline Company (Details) bbl / d in Thousands, $ in Millions |  | 3 Months Ended
--- | --- | ---
Feb. 15, 2017 USD ($) bbl / d | Mar. 31, 2017 USD ($)
Bakken Pipeline System |  |
Schedule of Equity Method Investments [Line Items] |  |
Crude oil throughput | bbl / d | 520 |
MarEn Bakken |  |
Schedule of Equity Method Investments [Line Items] |  |
Cash paid to acquire equity method investments |  | $ 500
MPLX LP | Bakken Pipeline System |  |
Schedule of Equity Method Investments [Line Items] |  |
Equity method investments, ownership percentage | 9.20% |
MPLX LP | MarEn Bakken |  |
Schedule of Equity Method Investments [Line Items] |  |
Cash paid to acquire equity method investments | $ 500 |
Equity method investments, ownership percentage | 25.00% |
MPC & Enbridge Energy Partners | Bakken Pipeline System |  |
Schedule of Equity Method Investments [Line Items] |  |
Percentage of ownership interest in joint venture acquired | 36.75% |
MPC & Enbridge Energy Partners | MarEn Bakken |  |
Schedule of Equity Method Investments [Line Items] |  |
Cash paid to acquire equity method investments | $ 2,000 |

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- Definition Pipeline Barrels Handled + References No definition available. + Details
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571 + Details
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- Definition The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence. + References Reference 1: 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=98514028&loc=d3e3213-108585 + Details
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