Quarterly Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, plant and equipment [Line Items]
Goodwill impairment									$ 0	$ 92,334	$ 139,444
Asset impairment charges	$ 2,357							$ 7,866
Selected Quarterly Financial Information [Abstract]
Total revenues	83,101	$ 71,598	$ 75,315	$ 65,552	$ 82,868	$ 70,714	$ 76,089	81,692	295,566	311,363	457,641
Net income	$ (10,673)	$ (7,821)	$ (6,372)	$ (15,593)	$ (12,138)	$ (15,971)	$ (4,680)	$ (105,349)	$ (40,459)	$ (138,138)	$ (146,630)
Net income per common unit	$ (0.29)	$ (0.22)	$ (0.18)	$ (0.46)	$ (0.36)	$ (0.47)	$ (0.14)	$ (3.11)	$ (1.13)	$ (4.07)	$ (4.36)
Net income per diluted common unit	$ (0.29)	$ (0.22)	$ (0.21)	$ (0.46)	$ (0.36)	$ (0.47)	$ (0.14)	$ (3.11)