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Stockholders' Equity - Additional Information (Detail) - USD ($)
1 Months Ended 12 Months Ended
Dec. 31, 2016
Mar. 31, 2011
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Dec. 20, 2016
Oct. 19, 2016
May 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Common stock, shares authorized (in shares) 90,000,000   90,000,000 90,000,000        
Common stock, shares outstanding (in shares) 27,206,162   27,206,162 25,772,507        
Preferred Stock, shares authorized (in shares)           10,000,000    
Preferred Stock, shares issued (in shares) 0   0 0        
Preferred Stock, shares outstanding (in shares) 0   0 0        
Compensation expense     $ 4,200,000 $ 4,000,000 $ 3,400,000      
Compensation expense, net of tax     2,900,000 2,800,000 2,900,000      
Unrecognized compensation cost $ 4,700,000   $ 4,700,000          
Weighted average remaining period     2 years          
Stock price $ 36.90   $ 36.90          
Fair market value of the shares     $ 3,800,000 $ 3,500,000 $ 3,800,000      
Stock repurchase program, authorized amount               $ 50,000,000
Repurchases of common stock (in shares)     177,053          
Treasury stock acquired, average cost per share (in USD per share)     $ 25.65          
Cash dividends declared (in USD per share)     0.60 $ 0.57 $ 0.46      
Cash dividends paid (in USD per share)     $ 0.60 $ 0.57        
Maximum [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Stock repurchase program, authorized amount             $ 30,000,000  
Restricted Stock [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Intrinsic value of stock awards $ 7,400,000   $ 7,400,000          
2004 Plan [Member] | Restricted Stock [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Shares subject to outstanding awards (in shares) 750,576   750,576          
2014 Plan [Member] | Restricted Stock [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Shares of common stock available for delivery pursuant to the grant of awards (in shares) 750,000   750,000          
Restricted shares for vesting period     5 years          
Convertible Notes [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Notes redemption date     Jan. 12, 2017          
Conversion of notes into shares, amount $ 39,300,000   $ 39,300,000          
Surrender of notes for conversion end date     Jan. 09, 2017          
Conversion of notes into additional common shares 1,500,000 36.0985 1,536,992