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Stock-Based Compensation - Additional Information (Detail) - USD ($)
$ / shares in Units, shares in Millions, $ in Millions
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares authorized under stock compensation plans 7.8    
Shares authorized under stock compensation plans Apr. 30, 2025    
Stock options vesting period 3 years    
Weighted average fair value of options granted (usd per share) $ 6.12 $ 7.16 $ 4.56
Aggregate intrinsic value of stock options outstanding $ 10.6    
Percentage of target shares earned     200.00%
Excess tax benefit from stock-based compensation 1.6 $ 2.2 $ 0.0
Restricted Stock      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Compensation expense related to share-based compensation plans 1.2 1.0 1.1
Unrecognized compensation cost related to stock options $ 0.8    
Weighted-average recognition period for unrecognized compensation cost 1 year 8 months 12 days    
Stock Options      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Compensation expense related to share-based compensation plans $ 2.0 1.7 1.5
Unrecognized compensation cost related to stock options $ 2.4    
Weighted-average recognition period for unrecognized compensation cost 1 year 9 months 18 days    
PSUs [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Unrecognized compensation cost $ 2.6 $ 3.6  
Weighted-average recognition period for unrecognized compensation cost 1 year 6 months 1 year 8 months 12 days  
Compensation expense related to share-based compensation plans $ 3.5 $ 3.4 $ 1.4
Minimum | PSUs [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Purchase price of common stock, percent 0.00%    
Maximum | PSUs [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Purchase price of common stock, percent 200.00%    
2013 Grants | PSUs [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock options vesting period 3 years    
Performance share units performance period 1 year    
Service requirement 2 years    
Percentage of target shares earned 200.00%    
2014 Grants | PSUs [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock options vesting period 3 years    
Performance share units performance period 2 years    
Service requirement 1 year    
Percentage of target shares earned 200.00%    
2015 Grants | PSUs [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock options vesting period 3 years    
Performance share units performance period 3 years