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Employee Benefit Plans (Details) $ / shares in Units, $ in Millions | 12 Months Ended
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Dec. 31, 2021 USD ($) Installment $ / shares shares | Dec. 31, 2020 USD ($) $ / shares shares | Dec. 31, 2019 USD ($) $ / shares shares
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contribution for defined contribution plan | $ 4.1 | $ 3.9 | $ 3.5
Employee Stock Ownership Plan, common stock, fair value | $ 28.1 |  |
Employee Stock Ownership Plan, common stock, shares outstanding (shares) | shares | 122,582 |  |
Nonqualified Deferred Compensation Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Deferred compensation expense | $ 0.1 | $ 0.4 | $ 0.3
Number of annual installments of deferred compensation (installment) | Installment | 2 |  |
Number of days after departure from board of directors for payment of deferred compensation (days) | 90 days |  |
Outside Directors |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Number of deferred common stock (shares) | shares | 6,944 | 10,593 | 10,738
Vested | $ / shares | $ 164.23 | $ 111.19 | $ 117.73

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