Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation - Additional Information (Details)

v3.10.0.1
Share-Based Compensation - Additional Information (Details)
12 Months Ended
Oct. 30, 2012
shares
Dec. 31, 2018
USD ($)
Installment
$ / shares
shares
Dec. 31, 2017
USD ($)
$ / shares
shares
Dec. 31, 2016
USD ($)
$ / shares
Restricted Stock [Member]        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Number of annual installments | Installment   3    
Weighted Average Grant Date Fair Value Per, Granted | $ / shares   $ 137.78 $ 90.16 $ 63.94
Weighted average grant date fair value per, vested | $   $ 6,200,000 $ 2,700,000 $ 0
Unrecognized stock-based compensation cost | $   $ 5,500,000    
Unrecognized compensation costs, weighted-average recognition periods   1 year 7 months 6 days    
Phantom shares vested   43,931    
Phantom Share Units (PSUs) [Member]        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized 1,000,000      
Share-based compensation arrangement vesting increment percentage 20.00%      
Share based compensation arrangement, employment period for eligibility of employees participation 10 years      
Employee Phantom Stock Plan [Member]        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Unrecognized stock-based compensation cost | $   $ 10,100,000    
Phantom Stock Plan [Member]        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Phantom shares vested   356,789 360,481  
Stock Incentive Plan 2016 [Member]        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized   2,000,000