Quarterly report pursuant to Section 13 or 15(d)

Stock Based Compensation - Additional Information (Detail)

v3.7.0.1
Stock Based Compensation - Additional Information (Detail) - USD ($)
3 Months Ended 6 Months Ended
Jan. 01, 2017
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Stock-based compensation expense   $ 414,000 $ 802,000 $ 919,000 $ 1,645,000
Unrecognized compensation cost related to unvested stock-based awards granted to employees under the stock option plans   $ 2,400,000   $ 2,400,000  
Unrecognized compensation cost related to unvested stock-based awards granted to employees under the stock option plans, period for recognition       2 years 1 month 6 days  
Stock options exercised       0  
Tax benefit realized upon exercise of option       $ 0  
2014 Equity Incentive Plan          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Remaining shares available for issuance   1,754,229   1,754,229  
2004 Employee Stock Purchase Plan          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Remaining shares available for issuance   203,165   203,165  
Additional shares authorized for issuance 100,000        
Plan participants purchased shares       31,624  
Average purchase price under 2004 Employee Stock Purchase Plan   $ 0.25   $ 0.25  
Cash proceeds       $ 7,000