QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
QUARTERLY FINANCIAL DATA (UNAUDITED)
Net revenue	$ 105,854	$ 111,055	$ 121,571	$ 98,449	$ 113,541	$ 110,730	$ 115,206	$ 99,621	$ 436,929	$ 439,098
Operating income	12,062	31,117	29,121	14,796	9,411	32,101	24,813	7,315	87,096	73,640
Net (loss) income	(7,788)	5,687	7,137	(2,979)	113,856	23,375	23,896	(22,522)
Consolidated net (loss) income attributable to common stockholders	$ (7,921)	$ 5,359	$ 6,591	$ (3,104)	$ 113,363	$ 23,044	$ 23,590	$ (22,555)	$ 925	$ 137,442
BASIC AND DILUTED NET (LOSS) INCOME ATTRIBUTABLE TO COMMON STOCKHOLDERS
Consolidated net (loss) income per share attributable to common stockholders - basic	$ (0.18)	$ 0.12	$ 0.15	$ (0.07)	$ 2.54	$ 0.51	$ 0.51	$ (0.48)	$ 0.02	$ 3.01
Consolidated net (loss) income per share attributable to common stockholders - diluted	$ (0.18)	$ 0.12	$ 0.14	$ (0.07)	$ 2.42	$ 0.49	$ 0.49	$ (0.48)	$ 0.02	$ 2.86
WEIGHTED AVERAGE SHARES OUTSTANDING
Weighted average shares outstanding - basic	44,172,147	44,315,077	45,061,821	45,001,767	44,663,033	45,128,341	46,033,402	46,757,386	44,699,586	45,647,696
Weighted average shares outstanding -diluted	44,172,147	46,118,702	45,701,655	45,001,767	46,874,741	47,462,358	48,438,693	46,757,386	47,921,671	48,000,957