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Stock-Based Compensation - Summary of Employee and Director Share Grant Activity (Details) - Restricted Stock - $ / shares
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Restricted Stock Grants      
Balance at the beginning of the period (in shares) 209,032 212,608 223,114
Granted (in shares) 99,802 95,671 109,081
Released (in shares) (96,248) (94,164) (110,724)
Cancelled (in shares) (12,808) (5,083) (8,863)
Balance at the end of the period (in shares) 199,778 209,032 212,608
Weighted-Average Grant-Date Fair Value      
Balance at the beginning of the period (in dollars per share) $ 95.86 $ 91.62 $ 80.02
Granted (in dollars per share) 132.75 98.81 101.52
Released (in dollars per share) 91.65 89.43 79.58
Cancelled (in dollars per share) 113.89 93.16 90.11
Balance at the end of the period (in dollars per share) $ 115.16 $ 95.86 $ 91.62