SHARE-BASED COMPENSATION - RSU Activity - Summary of Change (Details)	6 Months Ended
	Jun. 30, 2016 USD ($) $ / shares shares
Number of Restricted Stock Units [Roll Forward]
RSUs beginning	1,590,417
RSUs awarded	1,116,585
RSUs released	(595,717)
RSUs forfeited	(8,950)
RSUs ending	2,102,335
Weighted Average Purchase Price RSUs | $ / shares	$ 0
Weighted Average Remaining Contractual Term (Years) RSUs	1 year 10 months 24 days
Aggregate Intrinsic Value RSUs | $	$ 28,528,686
Number of RSUs vested and expected to vest	1,905,785
Weighted Average Purchase Price of RSUs vested and expected to vest | $ / shares	$ 0
Weighted Average Remaining Contractual Term (Years) of RUSs vested and expected to vest	1 year 10 months 24 days
Aggregate Intrinsic Value RSUs vested and expected to vest | $	$ 25,198,200
Number of RSUs exercisable	48,880
Weighted Average Purchase Price of RUSs exercisable | $ / shares	$ 0
Weighted Average Remaining Contractual Term (Years) of RUSs exercisable	0 years
Aggregate Intrinsic Value RSUs exercisable | $	$ 663,302
Weighted average remaining recognition period in years	2 years 8 months 12 days
Unamortized compensation expense, net of estimated forfeitures | $	$ 14,079,435