Quarterly report pursuant to Section 13 or 15(d)

Stock Based Compensation - Additional Information (Detail)

v3.2.0.727
Stock Based Compensation - Additional Information (Detail) - USD ($)
3 Months Ended 6 Months Ended
Jan. 01, 2015
Jun. 30, 2015
Jun. 30, 2014
Jun. 30, 2015
Jun. 30, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Stock-based compensation expense   $ 1,895,000 $ 1,468,000 $ 3,316,000 $ 2,734,000
Unrecognized compensation cost related to unvested stock-based awards granted to employees under the stock option plans   13,400,000   $ 13,400,000  
Unrecognized compensation cost related to unvested stock-based awards granted to employees under the stock option plans, period for recognition       2 years 8 months 12 days  
Non-employee stock-based compensation expense   $ 17,000 $ 19,000 $ 41,000 55,000
Total intrinsic value of stock options exercised       200,000 200,000
Cash received from stock option exercises       100,000 100,000
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   2,379,326   2,379,326  
2004 Employee Stock Purchase Plan          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Remaining shares available for issuance   206,231   206,231  
Additional shares authorized for issuance 100,000        
Plan participants purchased shares       74,673  
Average purchase price under 2004 Employee Stock Purchase Plan   $ 3.43   $ 3.43  
Cash proceeds       $ 300,000