Annual report pursuant to Section 13 and 15(d)

Common Stock - Additional Information 1 (Detail)

v3.3.1.900
Common Stock - Additional Information 1 (Detail)
$ / shares in Units, $ in Thousands, shares in Millions
12 Months Ended
Dec. 31, 2015
USD ($)
Right
$ / shares
shares
Dec. 31, 2014
USD ($)
$ / shares
shares
Dec. 31, 2013
USD ($)
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted average fair value of stock options granted | $ / shares $ 1.10 $ 6.52 $ 8.07
Unrecognized compensation expense related to stock options granted $ 1,800    
Estimated grant date fair value of stock options vested 1,300 $ 1,900 $ 1,800
Aggregate intrinsic value of options exercised 2,787 $ 51,100 $ 34,000
Aggregate intrinsic value of the outstanding options 350    
Aggregate intrinsic value of the exercisable outstanding options $ 0    
Reverse stock split One-for-eighteen reverse stock split    
Percentage of acquisition of company's common stock 15.00%    
Number of rights per share of common stock | Right 18    
Effect on diluted per share on options, restricted stock units and warrants | shares 5.8 7.0 3.0
Series A preferred stock [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Exercise price per Share | $ / shares $ 140    
Shareholder rights plan description One one-hundredth    
Stock options [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted-average period, restricted stock awards 2 years 1 month 6 days    
Stock options [Member] | Minimum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award expiration period 7 years    
Stock options [Member] | Maximum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award expiration period 10 years    
Stock options [Member] | Employees and consultants [Member] | Minimum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award vesting period 3 years    
Stock options [Member] | Employees and consultants [Member] | Maximum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award vesting period 4 years    
Stock options [Member] | Board of Directors [Member] | Minimum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award vesting period 1 year    
Stock options [Member] | Board of Directors [Member] | Maximum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award vesting period 3 years    
Restricted Stock Unit [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Award vesting period 4 years    
Weighted-average period, restricted stock awards 2 years 2 months 12 days    
Stock based compensation expense $ 1,100 $ 2,200 $ 1,100
Total unrecognized compensation expense related to the Company's restricted stock unit awards $ 2,000