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Stock-Based Compensation - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2016
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Approximate number of shares employees purchased under the Employee Stock Purchase Plan   422,687    
Stock Options Outstanding, Number 0 0 0  
2014 Stock Incentive Plan [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Total aggregate number of shares of common stock that may be issued 6,420,000 6,420,000    
Performance-Based Restricted Stock [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Vesting period   3 years    
Unrecognized compensation cost related to unvested awards $ 1,200,000 $ 1,200,000 $ 600,000  
Compensation cost recognition period for unvested awards 2 years      
Number of shares or rights issued   44,925 34,638  
Performance-Based Restricted Stock [Member] | Share-Based Compensation Award, Tranche One [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based Compensation vesting percentage   33.33%    
Performance-Based Restricted Stock [Member] | Share-Based Compensation Award, Tranche Two [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based Compensation vesting percentage   33.33%    
Performance-Based Restricted Stock [Member] | Share-Based Compensation Award, Tranche Three [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based Compensation vesting percentage   33.33%    
Stock Appreciation Rights [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Unrecognized compensation cost related to unvested awards $ 0 $ 0    
Maximum contractual term   10 years    
Fair value assumptions method used   Black-Scholes option-pricing model    
Number of shares or rights issued   0    
Weighted-average fair value of grants     $ 16.26 $ 17.78
Time-Based Restricted Stock [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Unrecognized compensation cost related to unvested awards $ 1,500,000 $ 1,500,000    
Compensation cost recognition period for unvested awards 1 year 7 months 6 days      
Total fair value of restricted shares vested   $ 1,700,000 $ 9,800,000 $ 3,900,000
Number of shares or rights issued   57,874 57,598 66,511
Employee Stock Purchase Plan [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Total aggregate number of shares of common stock that may be issued 600,000 600,000    
Percentage of market price on lesser of either first day of calendar quarter or last day of calendar quarter for purchase price   85.00%    
Percentage of gross compensation eligible employees may elect to participate in the plan 15.00% 15.00%    
Stock Options [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Maximum contractual term   10 years    
Minimum [Member] | Performance-Based Restricted Stock [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Percentage of target number of shares that will vest   0.00%    
Maximum [Member] | Performance-Based Restricted Stock [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Percentage of target number of shares that will vest   200.00% 200.00%