SHARE-BASED COMPENSATION - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Carry Unit Plan | Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value (in dollars per unit)	$ 3.17	$ 3.17		$ 3.17		$ 1.95
Share based compensation expense		$ 7,861	$ 7,993	$ 14,334	$ 25,494
2017 LTIP | Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation expense	$ 857
2017 LTIP | Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation expense		$ 7,817	$ 4,233	$ 15,134	$ 8,355