Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation - Additional Information (Detail)

v3.19.2
Stock-based Compensation - Additional Information (Detail) - 2012 Equity Incentive Plan [Member] - USD ($)
3 Months Ended 6 Months Ended
Jun. 20, 2019
Jun. 22, 2018
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]            
Number of additional shares authorized for issuance under an established share-based compensation plan 6,000,000 1,500,000        
Shares authorized under the incentive plan 8,250,000          
Maximum number of shares per individual per calendar year 1,000,000          
Number of stock options outstanding     2,488,293   2,488,293  
Stock option awards available for future grant     5,520,957   5,520,957  
Stock option awards     626,160 128,000 676,160 128,000
Weighted-average grant date fair value     $ 0.48 $ 1.52 $ 0.49 $ 1.52
Stock options vested         144,534  
Stock options forfeited         0  
Number of stock options, exercised         0  
Non-employee Directors [Member]            
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]            
Annual retainer amount for the threshold of stock precluded from selling         $ 270,000