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Stockholders' Equity - Additional Information (Detail) - USD ($)
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Apr. 25, 2018
Dec. 31, 2017
Apr. 26, 2017
May 16, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Common stock authorized (shares) 75,000,000          
Common stock par value (usd per share) $ 0.0001          
Preferred stock authorized (shares) 25,000,000          
Preferred stock par value (usd per share) $ 0.0001          
Options outstanding (shares) 0     0    
Common stock outstanding (shares) 19,956,847     20,135,514    
Preferred stock outstanding (shares) 0     0    
Stock repurchase authority         $ 10,000,000.0  
Amount spent to repurchase common stock $ 1,927,000          
Subsequent Event            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Dividend rate (usd per share)     $ 0.125      
Dividends declared     $ 2,600,000      
ESPP            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Number of shares authorized (shares) 250,000          
Award required holding period 2 years          
Stock purchased during period (shares) 0 0        
Performance-based RSUs | Restricted Stock Units            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Equity instruments other than options, nonvested (shares) 718,630     393,084    
Granted (shares) 334,035          
2011 Long Term Incentive Plan | Restricted Stock and Restricted Stock Units with Contingent Performance Requirements            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Equity instruments other than options, nonvested (shares) 362,980          
2011 Long Term Incentive Plan | Restricted Stock and Restricted Stock Units (RSUs)            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Compensation cost not yet recognized, share-based awards other than options $ 7,100,000          
Weighted-average period over which cost is expected to be recognized 2 years 15 days          
2012 Equity Plan            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Number of shares authorized (shares)       1,140,658   2,194,986
2012 Equity Plan | Restricted Stock            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Vesting period 1 year          
2012 Equity Plan | Restricted Stock Units            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Vesting period 3 years          
Granted (shares) 809,204          
2012 Equity Plan | Restricted Stock and Restricted Stock Units with Contingent Performance Requirements            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Vesting period 3 years          
Maximum | ESPP            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Offering period, maximum 6 months