Annual report pursuant to Section 13 and 15(d)

Equity Incentive Plans and Stock Based Compensation - Stock Options Outstanding and Exercisable by Exercise Price (Detail)

v3.7.0.1
Equity Incentive Plans and Stock Based Compensation - Stock Options Outstanding and Exercisable by Exercise Price (Detail)
12 Months Ended
Dec. 31, 2016
$ / shares
shares
$0.38-0.53  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices, Lower Limit $ 0.38
Range of Exercise Prices, Upper Limit $ 0.53
Options Outstanding, Number Outstanding | shares 1,153,000
Options Outstanding, Weighted Average Remaining Contractual Life (Years) 9 years 3 months 15 days
Options Outstanding, Weighted Average Exercise Price $ 0.49
Options Exercisable, Number Exercisable | shares 265,717
Options Exercisable, Weighted Average Exercise Price $ 0.49
$0.55-0.55  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices, Lower Limit 0.55
Range of Exercise Prices, Upper Limit $ 0.55
Options Outstanding, Number Outstanding | shares 1,414,999
Options Outstanding, Weighted Average Remaining Contractual Life (Years) 8 years 10 months 10 days
Options Outstanding, Weighted Average Exercise Price $ 0.55
Options Exercisable, Number Exercisable | shares 315,934
Options Exercisable, Weighted Average Exercise Price $ 0.55
$0.79-1.44  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices, Lower Limit 0.79
Range of Exercise Prices, Upper Limit $ 1.44
Options Outstanding, Number Outstanding | shares 1,769,313
Options Outstanding, Weighted Average Remaining Contractual Life (Years) 2 years 5 months 19 days
Options Outstanding, Weighted Average Exercise Price $ 1.35
Options Exercisable, Number Exercisable | shares 1,769,313
Options Exercisable, Weighted Average Exercise Price $ 1.35
$1.49-3.62  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices, Lower Limit 1.49
Range of Exercise Prices, Upper Limit $ 3.62
Options Outstanding, Number Outstanding | shares 2,472,416
Options Outstanding, Weighted Average Remaining Contractual Life (Years) 4 years 6 months 18 days
Options Outstanding, Weighted Average Exercise Price $ 2.67
Options Exercisable, Number Exercisable | shares 2,225,880
Options Exercisable, Weighted Average Exercise Price $ 2.57
$3.87-4.43  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices, Lower Limit 3.87
Range of Exercise Prices, Upper Limit $ 4.43
Options Outstanding, Number Outstanding | shares 1,430,358
Options Outstanding, Weighted Average Remaining Contractual Life (Years) 6 years 11 months 27 days
Options Outstanding, Weighted Average Exercise Price $ 4.36
Options Exercisable, Number Exercisable | shares 849,104
Options Exercisable, Weighted Average Exercise Price $ 4.33
$4.45-7.75  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices, Lower Limit 4.45
Range of Exercise Prices, Upper Limit $ 7.75
Options Outstanding, Number Outstanding | shares 2,701,659
Options Outstanding, Weighted Average Remaining Contractual Life (Years) 3 years 11 months 5 days
Options Outstanding, Weighted Average Exercise Price $ 6.00
Options Exercisable, Number Exercisable | shares 2,650,117
Options Exercisable, Weighted Average Exercise Price $ 6.02
$0.38-7.75  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices, Lower Limit 0.38
Range of Exercise Prices, Upper Limit $ 7.75
Options Outstanding, Number Outstanding | shares 10,941,745
Options Outstanding, Weighted Average Remaining Contractual Life (Years) 5 years 5 months 9 days
Options Outstanding, Weighted Average Exercise Price $ 3.00
Options Exercisable, Number Exercisable | shares 8,076,065
Options Exercisable, Weighted Average Exercise Price $ 3.47