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Loans and Allowance for Loan and Lease Losses - Additional Information (Details) $ in Thousands | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2022 USD ($) | Mar. 31, 2022 USD ($) Loan | Mar. 31, 2022 USD ($) Contract | Mar. 31, 2022 USD ($) DebtSecurityNumber | Dec. 31, 2021 USD ($) | Dec. 31, 2021 USD ($) Loan | Dec. 31, 2021 USD ($) Contract | Dec. 31, 2021 USD ($) DebtSecurityNumber | Mar. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |  |  |  |  |
Loans Pledged as Collateral | $ 69,300 | $ 69,300 | $ 69,300 | $ 69,300 | $ 66,600 | $ 66,600 | $ 66,600 | $ 66,600 |  |
Loans and Leases Receivable, Related Parties, Ending Balance | 300 |  |  |  | 300 |  |  |  |  |
Loans and Leases Receivable, Related Parties, Additions | 0 |  |  |  | 0 |  |  |  |  |
Loans and Leases Receivable, Related Parties, Proceeds | 2,000 |  |  |  | 100 |  |  |  |  |
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest | 2,200 | 2,200 | 2,200 | 2,200 | 2,000 | 2,000 | 2,000 | 2,000 |  |
Financing Receivable, Troubled Debt Restructuring | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 |  |
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans | 18 |  |  |  | 52 |  |  |  |  |
Interest Income Recorded | 6 | $ 6 | 6 | $ 6 | 30 | $ 30 | 30 | $ 30 |  |
Number of loans |  | 0 |  | 7 |  | 2 |  | 7 |  |
Financing Receivable, Restructuring Recorded Investment With Nonaccrual Status |  |  |  |  | 600 | $ 600 | 600 | $ 600 |  |
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Acquired During Period, Cash Flows Expected to be Collected at Acquisition | 0 | $ 0 | $ 0 | $ 0 | 0 | 0 | $ 0 | 0 |  |
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | Contract |  |  | 0 |  |  |  | 0 |  |  |
Loans, allowance for loan losses | 8,484 | 8,484 | $ 8,484 | 8,484 | 8,320 | 8,320 | $ 8,320 | 8,320 | $ 7,475 | $ 7,470
Restructured Loan Modified through Extended Maturity and Payment Schedule Modification [Member] |  |  |  |  |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |  |  |  |  |
Financing Receivable, Restructuring Recorded Investment With Nonaccrual Status | 500 | 500 | 500 | 500 |  |  |  |  |  |
Loans, allowance for loan losses | 7 | 7 | 7 | 7 | $ 7 | $ 7 | $ 7 | $ 7 |  |
Minimum [Member] |  |  |  |  |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |  |  |  |  |
Loans Modified in a Troubled Debt Restructuring, Individually Evaluated for Impairment, Principal Balance, Threshold | 500 | 500 | 500 | 500 |  |  |  |  |  |
Minimum [Member] | ALC [Member] |  |  |  |  |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |  |  |  |  |
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest | $ 50 | $ 50 | $ 50 | $ 50 |  |  |  |  |  |
Real Estate [Member] |  |  |  |  |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |  |  |  |  |
Percentage of Loan Portfolio | 51.60% | 51.60% | 51.60% | 51.60% | 54.00% | 54.00% | 54.00% | 54.00% |  |

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