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Equity-Based Compensation - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Percentage of performance share payout measured by total shareholder return   0.00%  
Percentage of performance share payout measured by return on invested capital 0.00% 0.00%  
Allocated Share-based Compensation Expense $ 1,490 $ 1,467  
Cash paid for minimum tax withholdings $ 220    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period 912    
Share-based Compensation Arrangements by Share-based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price $ 66.97    
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options 303,840    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price $ 63.19    
Performance shares      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Allocated Share-based Compensation Expense $ 533 596  
Restricted stock units      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Allocated Share-based Compensation Expense $ 422 292  
Shares issued (in shares) 13,221    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested Shares Settled 19,133    
Employee Stock Option      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Allocated Share-based Compensation Expense $ 535 579  
Options, Grants in Period, Gross 196,488    
Director [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Allocated Share-based Compensation Expense $ 700 $ 1,500  
Deferred Compensation Share-based Arrangements, Liability, Classified, Noncurrent 2,100   $ 3,600
Deferred Compensation Cash-based Arrangements, Liability, Classified, Noncurrent $ 3,200   $ 2,400
Minimum | Performance shares      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share Based Compensation Arrangement By Share Based Payment Award Outstanding Award As Percentage Of Shares Issued 0.00%    
Maximum | Performance shares      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share Based Compensation Arrangement By Share Based Payment Award Outstanding Award As Percentage Of Shares Issued 200.00%