STOCK OPTIONS - SUMMARY OF OPTION ACTIVITY - (Details)	3 Months Ended	9 Months Ended
	Sep. 30, 2016 USD ($) $ / shares shares	Sep. 30, 2016 USD ($) $ / shares shares
Summary of option activity - Shares
Outstanding at the beginning of year (in shares) | shares		3,253,310
Granted (in shares) | shares		308,250
Forfeited (in shares) | shares		(172,406)
Exercised (in shares) | shares		(135,205)
Outstanding at the end of period (in shares) | shares	3,253,949	3,253,949
Vested at the end of period (in shares) | shares		1,498,267
Vested and expected to vest at the end of period (in shares) | shares	2,676,307	2,676,307
Summary of option activity - Weighted Average Exercise Price
Outstanding at the beginning of year (in dollars per shares)		$ 7.47
Granted (in dollars per shares)		6.44
Forfeited (in dollars per shares)		9.55
Exercised (in dollars per shares)		1.41
Outstanding at the end of period (in dollars per shares)	$ 7.51	7.51
Vested at the end of period (in dollars per share)	7.52	7.52
Vested and expected to vest at the end of period (in dollars per share)	$ 7.52	$ 7.52
Option activity disclosures
Weighted Average Remaining Contractual Term - Outstanding		7 years 9 months
Weighted Average Remaining Contractual Term - Vested		6 years 6 months 15 days
Weighted Average Remaining Contractual Term - Vested and expected to vest		7 years 6 months 11 days
Aggregate Intrinsic Value - Outstanding (in dollars) | $	$ 2,413,000	$ 2,413,000
Aggregate Intrinsic Value - Vested (in dollars) | $	1,712,000	1,712,000
Aggregate Intrinsic Value - Vested and expected to vest (in dollars) | $	2,165	$ 2,165
Stock Option
Weighted average grant-date fair value of options granted		$ 5.39
Total fair value of options vested | $	1,012,000	$ 3,120,000
Total unrecognized compensation expense, related to non-vested share-based compensation arrangements | $	$ 6,685,000	$ 6,685,000
Period for unrecognized compensation expense is estimated to be recognized		2 years 6 months 26 days