Condensed Consolidated Statements of Changes in Partners' Capital (Deficit) (Unaudited) - USD ($) $ in Thousands	Total	Limited Partner [Member]	Preferred Partner [Member]	General Partner [Member]
Balance at Dec. 31, 2018	$ (6,896)	$ 370,972	$ 253,923	$ (631,791)
Net income (loss)	3,757	(2,581)	6,279	59
Equity-based incentive compensation	69	64		5
Distributions	(9,742)	(3,308)	(6,279)	(155)
Proceeds from sale of 63,340 common units pursuant to the Employee Unit Purchase Plan	73	73
Balance at Mar. 31, 2019	(12,739)	365,220	253,923	(631,882)
Balance at Dec. 31, 2019	(21,323)	356,777	253,923	(632,023)
Net income (loss)		(6,279)	6,279
Equity-based incentive compensation	108	105		3
Distributions	(8,082)	(1,675)	(6,279)	(128)
Proceeds from sale of 63,340 common units pursuant to the Employee Unit Purchase Plan	55	55
Balance at Mar. 31, 2020	$ (29,242)	$ 348,983	$ 253,923	$ (632,148)