Intangible Assets (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2017 USD ($) a	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 3,412	$ 3,458
Beginning balance	185,766	$ 199,741	$ 199,741
Disposals			(219)
Amortization	(3,412)		(13,756)
Ending balance	$ 182,354		$ 185,766
Customer Contracts
Finite-Lived Intangible Assets [Line Items]
Agreement term	15 years
Dedicated acreage | a	35,000
Useful life	15 years
Ending balance	$ 182,300
Marketing Contracts
Finite-Lived Intangible Assets [Line Items]
Amortization	$ 200