Acquisitions - Additional Information (Details) - USD ($) $ in Millions						1 Months Ended	12 Months Ended
		Nov. 17, 2015	Nov. 11, 2015	May. 18, 2015	Nov. 03, 2014	Jul. 31, 2015	Dec. 31, 2015		Jul. 01, 2015
Business Acquisition [Line Items]
Net proceeds from private placement	[1]						$ 297.4
Contribution from General Partner	[1]						6.1
General partners' capital account, additional units issued		187,755		156,986
Capital distribution to General Partner	[1]						1,002.1
Borrowings under credit facilities	[1]						458.2
Net assets acquired under common control							10.7
Contribution from General Partner	[2]						$ 6.1
Common units for initial public offering					46,000,000		9,387,755
Poseidon
Business Acquisition [Line Items]
Business acquisition, cash paid						$ 350.0
Business acquisition, closing date of acquisition							Jul. 01, 2015
Capital distribution to General Partner						319.5
Equity method investment percentage							36.00%		36.00%
Net assets acquired under common control						30.5	$ 10.7	[3]
Common Units
Business Acquisition [Line Items]
Net proceeds from private placement				$ 297.4
Common units for initial public offering		9,200,000
General Partner
Business Acquisition [Line Items]
Contribution from General Partner				$ 6.1
General partners' capital account, additional units issued				156,986
Common units for initial public offering		187,755
Five Year Revolver | Poseidon
Business Acquisition [Line Items]
Borrowings under credit facilities						$ 250.0
Line of credit facility, expiration period						5 years
364 Day Revolver | Poseidon
Business Acquisition [Line Items]
Borrowings under credit facilities						$ 100.0
Line of credit facility, expiration period						364 days
Zydeco
Business Acquisition [Line Items]
Business acquisition, transaction costs				$ 0.5
Zydeco | Shell Treasury Center West Inc | Five Year Revolver
Business Acquisition [Line Items]
Business acquisition, cash paid				70.8
Cash | Zydeco | Shell Treasury Center West Inc
Business Acquisition [Line Items]
Business acquisition, cash paid				$ 80.0
Purchase and Sale Agreement | Colonial
Business Acquisition [Line Items]
Additional cost method investment percentage acquired				1.388%
Purchase and Sale Agreement | Zydeco
Business Acquisition [Line Items]
Additional minority interest ownership percentage by parent acquired				19.50%
Purchase and Sale Agreement | Zydeco | Colonial
Business Acquisition [Line Items]
Business acquisition, cash paid				$ 448.0
Business acquisition, closing date of acquisition							May 12, 2015
Business acquisition, effective date of acquisition							Apr. 01, 2015
Zydeco and Colonial
Business Acquisition [Line Items]
Capital distribution to General Partner							$ 392.6
Pecten
Business Acquisition [Line Items]
Business acquisition, cash paid		$ 49.4
Business acquisition, closing date of acquisition							Nov. 17, 2015
Business acquisition, effective date of acquisition							Oct. 01, 2015
Business acquisition, transaction costs		$ 0.3	$ 390.0
Ownership interest (in percentage)		100.00%	100.00%
Business acquisition consideration amount		$ 390.0
Business combination capital distribution to general partner		290.0
Pecten | Common Units
Business Acquisition [Line Items]
Net proceeds from private placement		297.1
Pecten | General Partner
Business Acquisition [Line Items]
Contribution from General Partner		$ 6.1
Common units for initial public offering		187,755
Pecten | Revolving Credit Facility
Business Acquisition [Line Items]
Business acquisition, cash paid		$ 37.4

[1] The 2015 financial information has been retrospectively adjusted for the acquisition of the Shell Auger and Lockport Operations from January 1, 2015 through September 30, 2015.

[2] Prior period financial information has been retrospectively adjusted for the acquisition of the Shell Auger and Lockport Operations.

[3] We acquired an equity interest in Poseidon on July 1, 2015. For additional information regarding this transaction, see Note 3 - Acquisitions.