Annual report pursuant to Section 13 and 15(d)

STOCK-BASED COMPENSATION - Stock Options by Exercise Price (Details)

v3.8.0.1
STOCK-BASED COMPENSATION - Stock Options by Exercise Price (Details) - Employee stock option
 12 Months Ended
Dec. 31, 2017
$ / shares
shares
$1.68 - $2.14  
Stock options by exercise price  
Range of exercise prices, low end of the range (in dollars per share) $ 1.68
Range of exercise prices, high end of the range (in dollars per share) $ 2.14
Options Outstanding  
Number of Shares Underlying Options (in shares) | shares 4,351,726
Weighted-Average Remaining Contractual Life 7 years 3 months
Weighted-Average Exercise Price (in dollars per share) $ 2.12
Options Exercisable  
Number of Shares Underlying Options (in shares) | shares 2,389,173
Weighted Average Exercise Price (in dollars per share) $ 2.14
$2.27 - $2.74  
Stock options by exercise price  
Range of exercise prices, low end of the range (in dollars per share) 2.27
Range of exercise prices, high end of the range (in dollars per share) $ 2.74
Options Outstanding  
Number of Shares Underlying Options (in shares) | shares 3,682,677
Weighted-Average Remaining Contractual Life 7 years 9 months 29 days
Weighted-Average Exercise Price (in dollars per share) $ 2.60
Options Exercisable  
Number of Shares Underlying Options (in shares) | shares 2,439,679
Weighted Average Exercise Price (in dollars per share) $ 2.68
$2.89 - $3.67  
Stock options by exercise price  
Range of exercise prices, low end of the range (in dollars per share) 2.89
Range of exercise prices, high end of the range (in dollars per share) $ 3.67
Options Outstanding  
Number of Shares Underlying Options (in shares) | shares 3,449,971
Weighted-Average Remaining Contractual Life 5 years 6 months 26 days
Weighted-Average Exercise Price (in dollars per share) $ 3.49
Options Exercisable  
Number of Shares Underlying Options (in shares) | shares 2,859,448
Weighted Average Exercise Price (in dollars per share) $ 3.46
$3.79 - $6.51  
Stock options by exercise price  
Range of exercise prices, low end of the range (in dollars per share) 3.79
Range of exercise prices, high end of the range (in dollars per share) $ 6.51
Options Outstanding  
Number of Shares Underlying Options (in shares) | shares 3,831,410
Weighted-Average Remaining Contractual Life 4 years 7 months 17 days
Weighted-Average Exercise Price (in dollars per share) $ 5.62
Options Exercisable  
Number of Shares Underlying Options (in shares) | shares 2,961,860
Weighted Average Exercise Price (in dollars per share) $ 6.13
$6.55 - $9.62  
Stock options by exercise price  
Range of exercise prices, low end of the range (in dollars per share) 6.55
Range of exercise prices, high end of the range (in dollars per share) $ 9.62
Options Outstanding  
Number of Shares Underlying Options (in shares) | shares 4,068,512
Weighted-Average Remaining Contractual Life 2 years 3 months 15 days
Weighted-Average Exercise Price (in dollars per share) $ 7.90
Options Exercisable  
Number of Shares Underlying Options (in shares) | shares 4,068,512
Weighted Average Exercise Price (in dollars per share) $ 7.90
$9.80 - $26.45  
Stock options by exercise price  
Range of exercise prices, low end of the range (in dollars per share) 9.80
Range of exercise prices, high end of the range (in dollars per share) $ 26.45
Options Outstanding  
Number of Shares Underlying Options (in shares) | shares 1,023,844
Weighted-Average Remaining Contractual Life 1 month 17 days
Weighted-Average Exercise Price (in dollars per share) $ 26.02
Options Exercisable  
Number of Shares Underlying Options (in shares) | shares 1,023,844
Weighted Average Exercise Price (in dollars per share) $ 26.02
$1.68 - $26.45  
Stock options by exercise price  
Range of exercise prices, low end of the range (in dollars per share) 1.68
Range of exercise prices, high end of the range (in dollars per share) $ 26.45
Options Outstanding  
Number of Shares Underlying Options (in shares) | shares 20,408,140
Weighted-Average Remaining Contractual Life 5 years 2 months 23 days
Weighted-Average Exercise Price (in dollars per share) $ 5.45
Options Exercisable  
Number of Shares Underlying Options (in shares) | shares 15,742,516
Weighted Average Exercise Price (in dollars per share) $ 6.25