v3.3.0.814

Related Party Agreements and Transactions - Additional Information (Detail) $ in Millions		3 Months Ended		9 Months Ended		36 Months Ended
	Sep. 30, 2015 bbl	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) bbl	Sep. 30, 2014 USD ($)	Sep. 16, 2015 bbl
Related Party Transaction [Line Items]
Storage capacity (in number of barrels) | bbl				1,000,000
Revenue from Related Parties		$ 122.7	$ 114.1	$ 360.7	$ 336.0
MPC [Member]
Related Party Transaction [Line Items]
Revenue from Related Parties		$ 122.7	$ 114.1	$ 360.7	$ 336.0
Centennial [Member] | MPC [Member]
Related Party Transaction [Line Items]
Equity method investments, ownership percentage	50.00%	50.00%		50.00%
Muskegon [Member] | MPC [Member]
Related Party Transaction [Line Items]
Equity method investments, ownership percentage	60.00%	60.00%		60.00%
Operating Agreements [Member] | MPC [Member]
Related Party Transaction [Line Items]
Revenue from Related Parties				$ 0.6
Operating Agreements [Member] | Hardin Street Transportation LLC [Member]
Related Party Transaction [Line Items]
Term Of Agreements				1 year
Renewal Term Agreement				1 year
Revenue from Related Parties				$ 12.2
Storage Services Tank Farm [Member] | Commercial Agreements [Member] | MPC [Member]
Related Party Transaction [Line Items]
Storage capacity (in number of barrels) | bbl	2,626,000					1,386,000
Number of Tanks	4
Transportation Services Agreements [Member] | Cornerstone pipeline system and Utica build out projects [Member] | Commercial Agreements [Member] | MPC [Member]
Related Party Transaction [Line Items]
Term Of Agreements				15 years
Number of Renewals	2	2		2
Renewal Term Agreement				5 years

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- Definition

Renewal Term Agreement

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Storage Capacity

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Term Of Agreements

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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



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-SubTopic 10



-Section 50



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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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-Name Accounting Standards Codification



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