EARNINGS PER SHARE - (Information Related to EPS Calculation) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Numerator:
Net income	$ 37,924	$ 23,847	$ (5,879)	$ 1,834	$ 147,328	$ 10,516	$ 3,120	$ 5,659	$ 57,726	$ 166,623	$ 202,326
Net income attributable to noncontrolling interests									(714)	1,781	(23)
Net income attributable to common stockholders	$ 37,261	$ 23,365	$ (5,088)	$ 1,474	$ 149,121	$ 10,504	$ 3,120	$ 5,659	$ 57,012	$ 168,404	$ 202,303
Denominator:
Weighted average basic common shares outstanding (in shares)	43,075	43,066	42,573	42,976	42,860	42,845	40,373	39,799	43,036	41,364	39,492
Numerator:
Net income attributable to common stockholders	$ 37,261	$ 23,365	$ (5,088)	$ 1,474	$ 149,121	$ 10,504	$ 3,120	$ 5,659	$ 57,012	$ 168,404	$ 202,303
Denominator:
Weighted average basic common shares outstanding (in shares)	43,075	43,066	42,573	42,976	42,860	42,845	40,373	39,799	43,036	41,364	39,492
Restricted stock and stock options (in shares)									201	279	343
Warrants (in shares)									0	1,446	2,894
Weighted average diluted common shares outstanding	43,250	43,317	42,942	43,363	43,120	43,267	43,051	42,757	43,237	43,089	42,729
Basic income per share: (in dollars per share)	$ 0.87	$ 0.54	$ (0.12)	$ 0.03	$ 3.48	$ 0.25	$ 0.08	$ 0.14	$ 1.32	$ 4.07	$ 5.12
Diluted income per share: (in dollars per share)	$ 0.86	$ 0.54	$ (0.12)	$ 0.03	$ 3.46	$ 0.24	$ 0.07	$ 0.13	$ 1.32	$ 3.91	$ 4.73