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Employee Benefit Plans - Additional Information (Details) | 3 Months Ended | 4 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Sep. 30, 2020 USD ($) | Apr. 30, 2021 USD ($) | Sep. 30, 2021 USD ($) executive | Sep. 30, 2020 USD ($) | Dec. 31, 2020 USD ($)
Retirement Benefits [Abstract] |  |  |  |  |
Number of executives participating in SERP | executive |  |  | 2 |  |
Service cost of plan | $ 87,000 |  | $ 199,000 | $ 259,000 |
Interest cost of plan | $ 124,000 |  | 138,000 | $ 373,000 |
Supplemental executive retirement plan |  | $ 20,000,000 | 0 |  | $ 20,628,000
Employer contributions to benefit plans |  | $ 0 |  |  |
Defined benefit plan, recognized net gain (loss) due to terminations |  |  | $ 1,800,000 |  |

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