Quarterly report pursuant to Section 13 or 15(d)

Stock Based Compensation - Additional Information (Detail)

v3.5.0.2
Stock Based Compensation - Additional Information (Detail) - USD ($)
3 Months Ended 9 Months Ended
Jan. 01, 2016
Sep. 30, 2016
Sep. 30, 2015
Sep. 30, 2016
Sep. 30, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Stock-based compensation expense   $ 792,000 $ 1,476,000 $ 2,437,000 $ 4,792,000
Unrecognized compensation cost related to unvested stock-based awards granted to employees under the stock option plans   $ 4,000,000   $ 4,000,000  
Unrecognized compensation cost related to unvested stock-based awards granted to employees under the stock option plans, period for recognition       2 years 7 months 6 days  
Total intrinsic value of stock options exercised       $ 4,000 200,000
Cash received from stock option exercises       3,000 100,000
Tax benefit realized upon exercise of option       $ 0 $ 0
2014 Equity Incentive Plan          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Remaining shares available for issuance   1,358,638   1,358,638  
2004 Employee Stock Purchase Plan          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Remaining shares available for issuance   134,789   134,789  
Additional shares authorized for issuance 100,000        
Plan participants purchased shares       92,048  
Average purchase price under 2004 Employee Stock Purchase Plan   $ 0.24   $ 0.24  
Cash proceeds       $ 22,000