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Retirement Plans - Additional Information (Details) - USD ($)
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]      
Defined contribution plan, maximum annual contribution per employee, percent 400.00%    
Defined contribution plan, employer matching contribution, percent 100% of the first 3% and 50% of the next 2%    
Defined contribution plan, cost $ 2,623,000 $ 2,429,000 $ 1,881,000
Supplemental Employee Retirement Plans, Defined Benefit      
Defined Benefit Plan Disclosure [Line Items]      
Year of benefit 20 years    
Annual benefit amount $ 50,000    
Defined benefit plan, other cost (credit) 28,000 32,000 $ 36,000
Liability, defined benefit plan $ 441,000 $ 465,000