EARNINGS PER SHARE - Net Income and Weighted Average Shares Outstanding (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Earnings Per Share
Net income (loss) attributable to Class A common shareholders	$ 27,608	$ 3,313	$ 24,871	$ 46,698
Weighted average shares outstanding:
Basic (in shares)	62,148,362	52,922,487	60,976,046	51,091,977
Diluted (in shares)	63,347,690	53,348,858	61,875,010	51,388,851
Class A common stock
Earnings Per Share
Net income (loss) attributable to Class A common shareholders	$ 27,608	$ 3,313	$ 24,871	$ 46,698
Diluted Net income (loss) available for Class A common shareholders	$ 27,608	$ 3,313	$ 24,871	$ 46,698
Weighted average shares outstanding:
Basic (in shares)	62,148,362	52,922,487	60,976,046	51,091,977
Diluted (in shares)	63,347,690	53,348,858	61,875,010	51,388,851