STOCK-BASED COMPENSATION - RESTRICTED UNITS (Details) - Restricted stock units $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($) $ / shares shares
The 2004 Plan
Stock-based compensation
Vesting period	4 years
Annual vesting percentage	25.00%
Number of Shares
Non-vested restricted stock units at the beginning of the period (in shares) | shares	269,114
Vested (in shares) | shares	(165,524)
Forfeited (in shares) | shares	(16,292)
Non-vested restricted stock units at the end of the period (in shares) | shares	87,298
Weighted Average Grant Date Fair Value Per Share
Non-vested restricted stock units at the beginning of the period (in dollars per share) | $ / shares	$ 10.90
Vested (in dollars per share) | $ / shares	9.94
Forfeited (in dollars per share) | $ / shares	11.01
Non-vested restricted stock units at the end of the period (in dollars per share) | $ / shares	$ 12.69
Weighted Average Remaining Contractual Term
Non-vested restricted stock units at the end of the period	11 months 1 day
Additional disclosures
Total fair value of awards vested | $	$ 1.6
The 2014 Plan
Stock-based compensation
Vesting period	4 years
Annual vesting percentage	25.00%
Number of Shares
Non-vested restricted stock units at the beginning of the period (in shares) | shares	411,115
Granted (in shares) | shares	520,325
Vested (in shares) | shares	(281,110)
Forfeited (in shares) | shares	(80,839)
Non-vested restricted stock units at the end of the period (in shares) | shares	569,491
Weighted Average Grant Date Fair Value Per Share
Non-vested restricted stock units at the beginning of the period (in dollars per share) | $ / shares	$ 18.43
Granted (in dollars per share) | $ / shares	16.20
Vested (in dollars per share) | $ / shares	17.62
Forfeited (in dollars per share) | $ / shares	16.90
Non-vested restricted stock units at the end of the period (in dollars per share) | $ / shares	$ 17.01
Weighted Average Remaining Contractual Term
Non-vested restricted stock units at the end of the period	1 year 7 months 6 days
Additional disclosures
Total fair value of awards vested | $	$ 5.0