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Share-based Compensation - Additional Information (Detail) - USD ($)
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock option awards granted 90,000 0  
Options outstanding, shares 939,000   886,000
Stock options vested 36,250    
Aggregate fair value of stock option vested $ 2,500,000    
Weighted average grant date fair value of stock option awards $ 77.31    
Unrecognized share-based compensation expense $ 27,000,000    
Unrecognized compensation expense expected to be recognized 2 years 3 months 18 days    
Increase in additional paid-in capital   $ 1,300,000  
Deferred tax assets wrote off due to vested stock options not exercisable $ 0 1,600,000  
Decrease in additional-paid in capital 0 1,600,000  
Payments related to tax withholding for net-share settlement of share-based award 0 3,739,000  
2013 Equity Plan      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense recognized 3,100,000 1,500,000  
Payments related to tax withholding for net-share settlement of share-based award 0 3,700,000  
Adjustment to Additional paid in capital related to tax withholding for net-share settlement of share-based award $ 0 $ 3,700,000  
2013 Equity Plan | Class A      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation, stock authorized 1,700,000    
2013 Equity Plan | Class A | Employees, Officers, and Directors      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock option awards granted 90,000    
Options outstanding, shares 939,033    
Remaining shares of class A common stock authorized for future issuance 542,500