EARNINGS PER SHARE ("EPS") - Computation of Basic and Diluted Earnings (Loss) Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Numerator:
Net income from continuing operations	$ 22,060	$ 72,391	$ 91,372	$ 193,935	$ (3,153)	$ 8,382	$ (810)	$ 26,293	$ 379,758	$ 30,712	$ 6,112
Net income attributable to noncontrolling interests									(21)	(18)	(11)
Redeemable preferred stock dividends accumulated									(1,436)	0	0
Redeemable preferred stock dividends declared	(249)	(138)	(72)	(31)	(9)	0	0	0	(490)	(9)	0
Redeemable preferred stock redemptions	$ 2	$ 0	$ 0	$ 0					2	0	0
Numerator for basic net income from continuing operations available to common stockholders									377,813	30,685	6,101
Redeemable preferred stock dividends declared on dilutive shares									9	0	0
Numerator for dilutive net income from continuing operations available to common stockholders									377,822	30,685	6,101
Net income from discontinued operations					$ 792	$ 703	$ 1,668	$ 690	0	3,853	18,291
Numerator for basic net income available to common stockholders									377,813	34,538	24,392
Numerator for diluted net income available to common stockholders									$ 377,822	$ 34,538	$ 24,392
Denominator:
Basic weighted average shares outstanding									69,062	91,328	97,588
Effect of dilutive securities—contingently issuable shares									8
Diluted weighted average shares and common stock equivalents outstanding	55,917	57,876	78,871	84,048	84,048	87,045	96,683	97,662	69,070	91,328	97,588
Basic and diluted net income available to common stockholders per share:
Continuing operations (in usd per share)	$ 0.36	$ 1.25	$ 1.16	$ 2.31	$ (0.04)	$ 0.10	$ (0.01)	$ 0.27	$ 5.47	$ 0.34	$ 0.06
Discontinued operations (in usd per share)					0.01	0.01	0.02	0.01	0.00	0.04	0.19
Net income (in usd per share)	$ 0.36	$ 1.25	$ 1.16	$ 2.31	$ (0.03)	$ 0.10	$ 0.01	$ 0.28	$ 5.47	$ 0.38	$ 0.25