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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, 2021 USD ($) Loan Borrower Contract | Dec. 31, 2020 USD ($) Contract | Mar. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |
Loans Pledged as Collateral | $ 59,000 | $ 36,100 |  |
Loans and Leases Receivable, Related Parties, Ending Balance | 300 | 400 |  |
Loans and Leases Receivable, Related Parties, Additions | 0 | 100 |  |
Loans and Leases Receivable, Related Parties, Proceeds | 0 | 500 |  |
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest | 2,500 | 3,100 |  |
Financing Receivable, Troubled Debt Restructuring | 100 | 100 |  |
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans | 28 | 161 |  |
Interest Income Recorded | 5 | 42 |  |
Financing Receivable, Restructuring Recorded Investment With Nonaccrual Status | 0 | 0 |  |
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Acquired During Period, Cash Flows Expected to be Collected at Acquisition | $ 0 | $ 0 |  |
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | Contract | 0 | 0 |  |
Loans, allowance for loan losses | $ 7,475 | $ 7,470 | $ 5,954 | $ 5,762
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 |  |  |
Loans, allowance for loan losses | 1 | 1 |  |
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 |  |  |
Minimum [Member] | ALC [Member] |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest |  | 50 |  |
Paycheck Protection Program [Member] |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |
Loan, fixed interest rate | 1.00% |  |  |
Loan, aggregate principal balance | $ 14,800 |  |  |
Number of loans to small businesses | Loan | 154 |  |  |
Remaining Loan balance | $ 5,200 |  |  |
Number of companies | Borrower | 76 |  |  |
Amortized loan fees | $ 93 | 161 |  |
Net deferred loan fee | 387 |  |  |
Paycheck Protection Program [Member] | Two Year Term Loan [Member] |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |
Loan, aggregate principal balance | $ 9,600 |  |  |
Loan payment term | two years |  |  |
Paycheck Protection Program [Member] | Five Year Term Loan [Member] |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |
Loan, aggregate principal balance | $ 9,600 |  |  |
Loan payment term | five-year |  |  |
Paycheck Protection Program [Member] | Minimum [Member] |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |
Loan fee percentage | 1.00% |  |  |
Paycheck Protection Program [Member] | Maximum [Member] |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |
Loan fee percentage | 5.00% |  |  |
Financial Asset Acquired With Credit Deterioration [Member] |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |
Financing Receivable, Nonaccrual | $ 1,200 | 8,100 |  |
Deferred principal balance of loan reduced | $ 12,100 | $ 13,500 |  |
Deferred principal balance of loan reduced percentage | 1.80% | 2.10% |  |
Real Estate [Member] |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |
Percentage of Loan Portfolio | 56.50% | 56.10% |  |

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