v3.6.0.2
STOCK-BASED COMPENSATION - Plans by Exercise Price (Details)
12 Months Ended
Dec. 31, 2016
$ / shares
shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Number of Options Outstanding | shares 6,219,774
Weighted Average Remaining Contractual Term 6 years 5 months 1 day
Weighted Average Exercise Price per Share (in dollars per share) $ 6.15
Number of Options Exercisable | shares 4,086,597
Weighted Average Exercise Price per Share (in dollars per share) $ 5.67
$0.25 - $2.05  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Exercise price range, lower (in dollars per share) 0.25
Exercise price range, upper (in dollars per share) $ 2.05
Number of Options Outstanding | shares 1,183,702
Weighted Average Remaining Contractual Term 3 years 10 months 10 days
Weighted Average Exercise Price per Share (in dollars per share) $ 1.30
Number of Options Exercisable | shares 1,160,368
Weighted Average Exercise Price per Share (in dollars per share) $ 1.28
$2.28 - $6.00  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Exercise price range, lower (in dollars per share) 2.28
Exercise price range, upper (in dollars per share) $ 6.00
Number of Options Outstanding | shares 1,358,528
Weighted Average Remaining Contractual Term 6 years 4 months 13 days
Weighted Average Exercise Price per Share (in dollars per share) $ 5.27
Number of Options Exercisable | shares 1,104,796
Weighted Average Exercise Price per Share (in dollars per share) $ 5.22
$6.09 - $6.85  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Exercise price range, lower (in dollars per share) 6.09
Exercise price range, upper (in dollars per share) $ 6.85
Number of Options Outstanding | shares 1,041,000
Weighted Average Remaining Contractual Term 8 years 7 months 13 days
Weighted Average Exercise Price per Share (in dollars per share) $ 6.26
Number of Options Exercisable | shares 215,308
Weighted Average Exercise Price per Share (in dollars per share) $ 6.28
$7.15 - $7.48  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Exercise price range, lower (in dollars per share) 7.15
Exercise price range, upper (in dollars per share) $ 7.48
Number of Options Outstanding | shares 1,039,063
Weighted Average Remaining Contractual Term 7 years 4 months 24 days
Weighted Average Exercise Price per Share (in dollars per share) $ 7.17
Number of Options Exercisable | shares 417,772
Weighted Average Exercise Price per Share (in dollars per share) $ 7.17
$7.98 - $9.56  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Exercise price range, lower (in dollars per share) 7.98
Exercise price range, upper (in dollars per share) $ 9.56
Number of Options Outstanding | shares 73,826
Weighted Average Remaining Contractual Term 5 years 8 months 23 days
Weighted Average Exercise Price per Share (in dollars per share) $ 8.38
Number of Options Exercisable | shares 58,638
Weighted Average Exercise Price per Share (in dollars per share) $ 8.31
$9.58 - $11.31  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Exercise price range, lower (in dollars per share) 9.58
Exercise price range, upper (in dollars per share) $ 11.31
Number of Options Outstanding | shares 1,523,655
Weighted Average Remaining Contractual Term 6 years 4 months 2 days
Weighted Average Exercise Price per Share (in dollars per share) $ 9.81
Number of Options Exercisable | shares 1,129,715
Weighted Average Exercise Price per Share (in dollars per share) $ 9.82