EQUITY-BASED COMPENSATION - Schedule of Stock-based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Options
Beginning balance (shares)	3,716,579
Granted (shares)	1,061,587
Exercised (shares)	(2,025)
Expired and/or forfeited (shares)	(890,324)
Ending balance (shares)	3,885,817	3,716,579
Outstanding at end of year - vested and unvested expected to vest (shares)	3,799,575
Exercisable at end of year (shares)	2,242,727
Weighted Average Exercise Price
Beginning balance (in dollars per share)	$ 24.81
Granted (in dollars per share)	12.71
Exercised (in dollars per share)	14.56
Expired and/or forfeited (in dollars per share)	22.93
Ending balance (in dollars per share)	21.94	$ 24.81
Outstanding at end of year - vested and unvested expected to vest (in dollars per share)	22.12
Exercisable at end of year (in dollars per share)	$ 25.76
Stock Option Activity, Additional Disclosures
Weighted Average Remaining Contractual Term, Outstanding	6 years 9 months 18 days	7 years 3 months 18 days
Weighted Average Remaining Contractual Term, Outstanding at end of year - vested and unvested expected to vest	6 years 9 months 18 days
Weighted Average Remaining Contractual Term, Exercisable at end of year	5 years 6 months
Aggregate Intrinsic Value, Outstanding at end of year	$ 776
Aggregate Intrinsic Value, Outstanding at end of year, vested and unvested expected to vest	701
Aggregate Intrinsic Value, Exercisable at end of year	$ 116