NET INCOME (LOSS) PER SHARE ATTRIBUTABLE TO CLASS A COMMON SHAREHOLDERS (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Apr. 30, 2014
Numerator:
Net income (loss) attributable to holders of shares of Class A common stock - basic	$ 33,104	$ (3,012)
Class A common stock
Numerator:
Net income (loss) attributable to holders of shares of Class A common stock - basic	33,104	(3,012)
Net income (loss) attributable to holders of shares of Class A common stock - diluted	$ 33,104	$ (3,012)
Denominator:
Weighted average shares of Class A common stock outstanding - basic	20,021,652	15,911,819
Weighted average number of incremental shares issuable from unvested restricted stock, RSUs and stock options, as calculated using the treasury stock method	1,340,919
Weighted average shares of Class A common stock outstanding-diluted	21,362,571	15,911,819
Net income (loss) per share attributable to holders of shares of Class A common stock
Basic (in dollars per share)	$ 1.65	$ (0.19)
Diluted (in dollars per share)	$ 1.55	$ (0.19)
Number of shares of common stock to be issued upon exchange of a partnership unit	1		1
Fully diluted shares of common stock outstanding if all Class A partnership units were to be exchanged for common stock immediately following the reorganization	55,481,167	54,250,854
Class A common stock | Stock options
Net income (loss) per share attributable to holders of shares of Class A common stock
Number of antidilutive securities excluded from calculation of diluted income (loss) per share		3,296,906
Class A common stock | Restricted stock and RSUs
Net income (loss) per share attributable to holders of shares of Class A common stock
Number of antidilutive securities excluded from calculation of diluted income (loss) per share	1,380	2,315,512