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Restructuring Charges - Additional Information (Details) $ in Thousands |  | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Sep. 03, 2021 Branch EmploymentPosition | Sep. 30, 2021 Branch | Dec. 31, 2021 USD ($) Employee | Mar. 31, 2022 USD ($) | Dec. 31, 2020 Employee
Restructuring Cost And Reserve [Line Items] |  |  |  |  |
Number of full time employees | Employee |  |  | 8 |  | 81
ALC [Member] |  |  |  |  |
Restructuring Cost And Reserve [Line Items] |  |  |  |  |
Number of office closed | Branch | 20 | 20 |  |  |
Number of full-time employment positions eliminated | EmploymentPosition | 56 |  |  |  |
Pre-tax charges of restructuring |  |  | $ 904 |  |
ALC [Member] | Scenario Forecast [Member] |  |  |  |  |
Restructuring Cost And Reserve [Line Items] |  |  |  |  |
Restructuring charges expects to incur |  |  |  | $ 100 |

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