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Loans and Allowance for Loan and Lease Losses - Additional Information (Details) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 USD ($) Loan Contract | Dec. 31, 2019 USD ($) Contract | Dec. 31, 2018 USD ($) | Aug. 31, 2018 USD ($)
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |
Loans Pledged as Collateral | $ 36,100 | $ 34,600 |  |
Loans and Leases Receivable, Related Parties, Ending Balance | 400 | 900 |  |
Loans and Leases Receivable, Related Parties, Additions | 0 | 100 |  |
Loans and Leases Receivable, Related Parties, Proceeds | 500 | 22 |  |
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance, Total |  |  |  | $ 2,900
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount, Net |  |  |  | $ 2,800
Certain Loans Acquired in Transfer, Accretable Yield | 0 | 0 |  |
Loans | 650,123 | 556,053 |  |
Non-accruing loans | $ 3,086 | 3,723 |  |
Percentage of loan balance to Major Franchises | 100.00% |  |  |
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest | $ 3,100 | 3,700 |  |
Financing Receivable, Troubled Debt Restructuring | 100 | 100 |  |
Impaired loans with no related allowance recorded, carrying amount | 7,009 | 2,861 |  |
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans | 161 | 41 |  |
Interest Income Recorded | 42 | 147 |  |
Financing Receivable, Restructuring Recorded Investment With Nonaccrual Status | 0 | 16 |  |
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 | $ 7,470 | $ 5,762 | $ 5,055 |
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 | $ 14,000 |  |  |
Number of loans to small businesses | Loan | 167 |  |  |
Remaining Loan balance | $ 11,900 |  |  |
Paycheck Protection Program [Member] | Two Year Term Loan [Member] |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |
Loan, aggregate principal balance | $ 13,800 |  |  |
Loan payment term | two-year |  |  |
Paycheck Protection Program [Member] | Five Year Term Loan [Member] |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |
Loan, aggregate principal balance | $ 200 |  |  |
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] |  |  |  |
Loans | $ 160 | 175 |  |
Non-accruing loans | 200 |  | $ 200 |
Deferred principal balance of loan reduced | $ 8,100 |  |  |
Deferred principal balance of loan reduced percentage | 1.20% |  |  |
Impaired loans with no related allowance recorded, carrying amount | $ 200 | 200 |  |
Financial Asset Acquired With Credit Deterioration [Member] | Substandard [Member] |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |
Loans | $ 200 | $ 200 |  |
Real Estate [Member] |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |
Percentage of Loan Portfolio | 56.10% | 62.80% |  |

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