Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation - Activity (Details)

v3.22.0.1
Share-Based Compensation - Activity (Details) - USD ($)
3 Months Ended 12 Months Ended
Feb. 16, 2021
Feb. 17, 2020
Feb. 18, 2019
Mar. 31, 2021
Dec. 31, 2021
Dec. 31, 2020
Stock Options, Number of Shares            
Converted/Exercised (in shares)         (53,275) (19,242)
Stock options, additional disclosures            
Weighted average remaining contractual term for vested stock options         5 years 8 months 12 days  
Unrecognized share-based compensation expense            
Restricted stock awards, Unrecognized compensation expense         $ 10,574,000  
Restricted stock awards, Weighted average remaining vesting period         9 months 18 days  
Stock options, Unrecognized compensation expense         $ 1,317,000  
Stock options, Weighted average remaining vesting period         1 year  
Total unrecognized compensation expense related to unvested awards         $ 11,891,000  
Restricted Stock Awards            
Restricted Stock Awards, Number of Shares            
Balance at beginning of period (in shares)       324,800 324,800  
Granted (in shares)         74,600  
Converted/Exercised (in shares)         (144,700)  
Forfeited/Expired (in shares)         (10,300)  
Balance at end of period (in shares)         244,400 324,800
Restricted Stock Awards, Weighted Average Grant Date Fair Value Per Share            
Balance at beginning of period (in dollars per share)       $ 87.79 $ 87.79  
Granted (in dollars per share)         246.50  
Converted/Exercised (in dollars per share)         81.76  
Forfeited/Expired (in dollars per share)         93.63  
Balance at end of period (in dollars per share)         $ 119.41 $ 87.79
Assumptions used to estimate the fair values of the awards granted:            
Measurement period (years)         2 years 10 months 13 days 2 years 10 months 17 days
Risk free interest rate (as a percent)         0.22% 1.40%
Dividend yield (as a percent)         0.00% 0.00%
Estimated fair value of market-based RSAs at grant date (in dollars per share)         $ 298.66 $ 158.24
Restricted Stock Awards | Performance-based conditions            
Restricted stock awards, additional disclosures            
Grant date fair value $ 2,552,000 $ 2,675,000 $ 2,184,000      
Restricted Stock Awards | Performance-based conditions | Payout Range-0%            
Restricted stock awards, additional disclosures            
Payout range (as a percent) 0.00% 0.00% 0.00%      
Restricted Stock Awards | Performance-based conditions | Payout Range-25%            
Restricted stock awards, additional disclosures            
Payout range (as a percent) 25.00% 25.00% 25.00%      
Related expenses $ 638,000 $ 669,000 $ 546,000      
Restricted Stock Awards | Performance-based conditions | Payout Range-100%            
Restricted stock awards, additional disclosures            
Payout range (as a percent) 100.00% 100.00% 100.00%      
Related expenses $ 2,552,000 $ 2,675,000 $ 2,184,000      
Restricted Stock Awards | Performance-based conditions | Payout Range-200%            
Restricted stock awards, additional disclosures            
Payout range (as a percent) 200.00% 200.00% 200.00%      
Related expenses $ 5,104,000 $ 5,350,000 $ 4,368,000      
RSAs granted February 19, 2018 | Performance-based conditions            
Restricted stock awards, additional disclosures            
Cumulative period of achievement       3 years    
Cumulative achievement percentage       200.00%    
Total compensation expense recognized over the performance period, net of forfeitures       $ 3,700,000    
Stock Options            
Stock Options, Number of Shares            
Balance at beginning of period (in shares)       239,700 239,700  
Granted (in shares)         24,100  
Converted/Exercised (in shares)         (53,300)  
Balance at end of period (in shares)         210,500 239,700
Stock Options, Weighted Average Grant Date Fair Value Per Share            
Balance at beginning of period (in dollars per share)       $ 24.33 $ 24.33  
Granted (in dollars per share)         89.59  
Converted/Exercised (in dollars per share)         22.15  
Balance at end of period (in dollars per share)         32.35 $ 24.33
Stock Options, Weighted Average Exercise Price Per Share            
Balance at beginning of period (in dollars per share)       $ 68.86 68.86  
Granted (in dollars per share)         214.58  
Converted/Exercised (in dollars per share)         61.87  
Balance at end of period (in dollars per share)         $ 87.30 $ 68.86
Stock options, additional disclosures            
Aggregate intrinsic value         $ 39,692,400 $ 27,612,100
Converted/Exercised aggregate intrinsic value         $ 7,303,300  
Exercisable, Number of shares         114,300  
Exercisable, Weighted Average Grant Date Fair Value Per Share         $ 20.88  
Exercisable Weighted Average Exercise Price Per Share         $ 57.55  
Exercisable, Aggregate Intrinsic Value         $ 24,964,800  
Assumptions used to estimate the fair values of the awards granted:            
Risk free interest rate (as a percent)         0.76% 1.53%
Expected volatility using historical return volatility and implied volatility (as a percent)         43.29% 31.50%
Expected life (in years)         6 years 6 years
Dividend yield (as a percent)         0.00% 0.00%
Estimated fair value of market-based RSAs at grant date (in dollars per share)         $ 89.59 $ 39.49