EARNINGS PER SHARE - Net Income and Weighted Average Shares Outstanding (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Weighted average shares outstanding:
Basic (in shares)	85,135,685	62,148,362	79,416,957	60,976,046
Diluted (in shares)	85,476,266	63,347,690	109,857,679	61,875,010
Class A common stock
Earnings Per Share
Net income (loss) attributable to Class A common shareholders	$ 24,039	$ 27,608	$ 48,172	$ 24,871
Diluted Net income (loss) available for Class A common shareholders	$ 24,039	$ 27,608	$ 65,275	$ 24,871
Weighted average shares outstanding:
Basic (in shares)	85,135,685	62,148,362	79,416,957	60,976,046
Diluted (in shares)	85,476,266	63,347,690	109,857,679	61,875,010