CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' DEFICIT - USD ($) $ in Thousands	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income [Member]	Accumulated Deficit [Member]	Noncontrolling Interest [Member]	Total	Class A Common Stock [Member]	Class B Common Stock [Member]
Beginning balance at Dec. 31, 2015	$ 3,229	$ 37	$ (128,362)	$ 635	$ (124,383)	$ 65	$ 13
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		0	(7,175)	3,506	(3,669)
Foreign currency translation gain (loss)	0	(12)	0	0	(12)	0	0
Distributions	0	0	0	(1,912)	(1,912)
Ending balance at Dec. 31, 2016	3,229	25	(135,537)	2,229	(129,976)	65	13
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	0	0	(5,833)	2,335	(3,498)
Gain on extinguishment of subordinated debt		0	0	0	1,031
Stock-based compensation		0	0	0	50
Foreign currency translation gain (loss)	0	7	0	0	7
Distributions	0	0	0	(3,651)	(3,651)
Ending balance at Dec. 31, 2017	4,310	32	(141,370)	913	(136,037)	65	13
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	0	0	(1,640)	3,377	1,737
Foreign currency translation gain (loss)	0	(15)	0	0	(15)
Distributions	0	0	0	(1,669)	(1,669)
Ending balance at Dec. 31, 2018	4,310	17	(139,129)	2,621	(132,103)	$ 65	$ 13
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment due to change in accounting policy	$ 0	$ 0	$ 3,881	$ 0	$ 3,881