EARNINGS PER SHARE - Net Income and Weighted Average Shares Outstanding (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Earnings Per Share
Net income (loss) attributable to Class A common shareholders	$ 2,802	$ 34,210	$ (2,737)	$ 43,384
Weighted average shares outstanding
Basic (in shares)	61,170,006	50,335,095	60,383,447	50,161,553
Diluted (in shares)	61,976,962	50,929,538	60,383,447	98,148,577
Class A common stock
Earnings Per Share
Net income (loss) attributable to Class A common shareholders	$ 2,802	$ 34,210	$ (2,737)	$ 43,384
Diluted Net income (loss) available for Class A common shareholders	$ 2,802	$ 34,210	$ (2,737)	$ 83,065
Weighted average shares outstanding
Basic (in shares)	61,170,006	50,335,095	60,383,447	50,161,553
Diluted (in shares)	61,976,962	50,929,538	60,383,447	98,148,577