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Stock-Based Compensation - Additional Information (Detail)
12 Months Ended
Dec. 31, 2016
USD ($)
plan
$ / shares
shares
Dec. 31, 2015
USD ($)
$ / shares
shares
Dec. 31, 2014
USD ($)
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of incentive plans | plan 2    
Options, Granted (in shares) | shares 123,500    
Weighted-average fair value of grants (in dollars per share) | $ / shares $ 6.53    
Outstanding at end of period, Weighted average remaining contractual term 4 years 4 months 24 days    
Total fair value of options expensed before tax benefits $ 0 $ 0 $ 0
Stock Options      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Options, Granted (in shares) | shares 123,500 73,000 71,000
Weighted-average fair value of grants (in dollars per share) | $ / shares $ 6.53 $ 10.63 $ 12.62
Expiration period from date of grant 7 years    
Option vesting term 4 years    
Aggregate intrinsic value of stock options exercised $ 1,300,000 $ 2,300,000 $ 1,000,000
Cash received from the exercise of options 2,100,000 3,100,000 2,300,000
Tax benefits realized for the tax deductions from options exercised $ 500,000 900,000 400,000
Options vested (in shares) | shares 439,550    
Weighted average exercise price (in dollars per share) | $ / shares $ 20.07    
Aggregate intrinsic value $ 2,400,000    
Outstanding at end of period, Weighted average remaining contractual term 4 years 4 months 24 days    
Share-based compensation expense $ 800,000 1,200,000 1,500,000
Unrecognized compensation cost related to stock option $ 1,300,000    
Weighted average period 2 years 3 months 18 days    
Total fair value of options expensed before tax benefits $ 900,000 1,300,000 1,300,000
Restricted Stock Units      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Option vesting term 3 years    
Share-based compensation expense $ 1,800,000 $ 1,800,000 $ 1,300,000
Weighted average period 1 year 8 months 12 days    
Awards, Granted (in shares) | shares 139,450 108,500 86,300
Weighted average grant date fair value (in dollars per share) | $ / shares $ 15.97 $ 25.15 $ 24.74
Vesting percentage in year one 33.00%    
Vesting percentage in year two 33.00%    
Vesting percentage in year three 34.00%    
Compensation not yet recognized $ 2,200,000    
Fair value of awards vested in period 1,300,000 $ 1,800,000 $ 1,300,000
Tax benefit realized on vesting of options 700,000 700,000 500,000
Performance Stock Units      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense $ 400,000 $ 500,000 $ 1,000,000
Weighted average period 1 year 3 months 18 days    
Awards, Granted (in shares) | shares 62,500 64,000 67,500
Weighted average grant date fair value (in dollars per share) | $ / shares $ 15.92 $ 25.51 $ 24.90
Compensation not yet recognized $ 1,100,000    
Fair value of awards vested in period 1,100,000 $ 900,000.0 $ 0
Tax benefit realized on vesting of options $ 200,000 $ 300,000.0 $ 0
2007 Plan      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of shares authorized (in shares) | shares 1,200,000    
Shares reserved for future issuance other than stock options | shares 400,000    
Shares reserved for future issuance | shares 78,417    
2013 Plan      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of shares authorized (in shares) | shares 1,040,000    
Shares reserved for future issuance | shares 320,172