Earnings Per Unit - Computation of Basic and Diluted Earnings per Unit (Details) - USD ($) $ / shares in Units, shares in Thousands, $ 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
Earnings Per Share Basic [Line Items]
NET INCOME (LOSS)	$ 19,362	$ 22,034	$ 54,174	$ 61,583	$ (7,286)	$ 37,535	$ (20,810)	$ 10,749	$ 157,153	$ 20,188	$ (101,305)
Net income attributable to noncontrolling interests subsequent to initial public offering									34	12	1,260
Distributions on Series A redeemable preferred units subsequent to initial public offering									(3,117)	(5,763)	(7,522)
Distributable Preferred Stock Dividends									1,925	0	0
NET INCOME (LOSS) ATTRIBUTABLE TO THE GENERAL PARTNER AND COMMON AND SUBORDINATED UNITS SUBSEQUENT TO INITIAL PUBLIC OFFERING	16,779	21,388	53,518	60,460	(8,614)	36,219	(22,111)	8,943	152,145	14,437	(108,017)
Allocation of net loss subsequent to initial public offering attributable to:
General partner interest									0	0	0
NET INCOME (LOSS) ATTRIBUTABLE TO THE GENERAL PARTNER AND COMMON AND SUBORDINATED UNITS SUBSEQUENT TO INITIAL PUBLIC OFFERING	$ 16,779	$ 21,388	$ 53,518	$ 60,460	$ (8,614)	$ 36,219	$ (22,111)	$ 8,943	152,145	14,437	(108,017)
Common Units
Allocation of net loss subsequent to initial public offering attributable to:
Allocation of loss									$ 98,389	$ 24,669	$ (54,326)
Net loss attributable to common and subordinated units per unit:
Per unit (basic) (in usd per share)	$ 0.15	$ 0.16	$ 0.33	$ 0.37	$ 0.01	$ 0.24	$ (0.08)	$ 0.09	$ 1.01	$ 0.26	$ (0.56)
Weighted average units outstanding, basic (in shares)									97,400	96,073	96,182
Per unit (diluted) (in usd per share)	0.15	0.16	0.33	0.37	0.01	0.24	(0.08)	0.09	$ 1.01	$ 0.26	$ (0.56)
Weighted average units outstanding, diluted (in shares)									97,400	96,243	96,182
Subordinated Units
Allocation of net loss subsequent to initial public offering attributable to:
Allocation of loss									$ 53,756	$ (10,232)	$ (53,691)
Net loss attributable to common and subordinated units per unit:
Per unit (basic) (in usd per share)	0.03	0.05	0.22	0.26	(0.11)	0.14	(0.15)	0.01	$ 0.56	$ (0.11)	$ (0.56)
Weighted average units outstanding, basic (in shares)									95,149	95,138	95,057
Per unit (diluted) (in usd per share)	$ 0.03	$ 0.05	$ 0.22	$ 0.26	$ (0.11)	$ 0.14	$ (0.15)	$ 0.01	$ 0.56	$ (0.11)	$ (0.56)
Weighted average units outstanding, diluted (in shares)									95,149	95,138	95,057
Predecessor
Earnings Per Share Basic [Line Items]
NET INCOME (LOSS)									$ 0	$ 0	$ (450)