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Description of Business and Basis of Presentation - Additional Information (Detail) |  |  |  | 3 Months Ended
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Feb. 01, 2018 | Sep. 01, 2017 | Mar. 01, 2017 | Mar. 31, 2018
Description Of Business And Basis Of Presentation [Line Items] |  |  |  |
Number of reportable segments |  |  |  | 2
Illinois Extension |  |  |  |
Description Of Business And Basis Of Presentation [Line Items] |  |  |  |
Equity method investment, ownership percentage |  | 35.00% |  | 35.00%
LOOP |  |  |  |
Description Of Business And Basis Of Presentation [Line Items] |  |  |  |
Equity method investment, ownership percentage |  | 41.00% |  | 41.00%
LOCAP |  |  |  |
Description Of Business And Basis Of Presentation [Line Items] |  |  |  |
Equity method investment, ownership percentage |  | 59.00% |  | 59.00%
Explorer |  |  |  |
Description Of Business And Basis Of Presentation [Line Items] |  |  |  |
Equity method investment, ownership percentage |  | 25.00% |  | 25.00%
LOOP LOCAP SAX and Explorer Llc |  |  |  |
Description Of Business And Basis Of Presentation [Line Items] |  |  |  |
Effective date of acquisition |  | Sep. 01, 2017 |  |
HST & WHC & MPLXT |  |  |  |
Description Of Business And Basis Of Presentation [Line Items] |  |  |  |
Effective date of acquisition |  |  | Mar. 01, 2017 |
Refining Logistics & Fuels Distribution |  |  |  |
Description Of Business And Basis Of Presentation [Line Items] |  |  |  |
Effective date of acquisition | Feb. 01, 2018 |  |  |

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- Definition Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e845-128460 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e848-128460 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + 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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