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Stock Plans - Summary of Restricted Stock and Unit Activity (Details) - Restricted Stock Activity
6 Months Ended
Jun. 30, 2021
$ / shares
shares
Shares  
Unvested, beginning balance (in shares) | shares 146,191
Granted (in shares) | shares 35,686
Vested (in shares) | shares (51,753)
Forfeited (in shares) | shares (1,035)
Unvested, ending balance (in shares) | shares 129,089
Weighted Average Exercise Price (dollars per share)  
Unvested, beginning balance (dollars per share) | $ / shares $ 105.83
Granted (dollars per share) | $ / shares 169.54
Vested (dollars per share) | $ / shares 92.84
Forfeited (dollars per share) | $ / shares 139.08
Unvested, ending Balance (dollars per share) | $ / shares $ 128.39