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Share-Based Compensation - Summary of Restricted Stock Award Activity for Employees and Non-Employee Directors (Details) - $ / shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Granted    
Forfeited    
Weighted Average Grant Date Fair Value Per Share, Ending Balance $ 174.44    
Restricted Stock [Member]      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Beginning Balance 91,181    
Granted 75,048    
Vested (51,675)    
Forfeited (5,400)    
Ending Balance 109,154 91,181  
Weighted Average Grant Date Fair Value Per Share, Beginning Balance $ 107.06    
Weighted Average Grant Date Fair Value Per, Granted 144.89 $ 137.78 $ 90.16
Weighted Average Grant Date Fair Value Per , Vested 98.11    
Weighted Average Grant Date Fair Value Per Share, Forfeited 133.91    
Weighted Average Grant Date Fair Value Per Share, Ending Balance $ 135.97 $ 107.06