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Loans and Allowance for Loan Losses - Additional Information (Details) | 6 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jun. 30, 2020 USD ($) Loan Contract | Dec. 31, 2019 USD ($) Contract | Aug. 31, 2018 USD ($)
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |
Loans Pledged as Collateral | $ 32,600,000 | $ 34,600,000 |
Loans and Leases Receivable, Related Parties, Ending Balance | 500,000 | 900,000 |
Loans and Leases Receivable, Related Parties, Additions | 0 | 100,000 |
Loans and Leases Receivable, Related Parties, Proceeds | 400 | 22,000,000 |
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Outstanding Balance, Total |  |  | $ 2,900,000
Purchased credit impaired loans |  |  | $ 2,800,000
Certain Loans Acquired in Transfer, Accretable Yield | 0 | 0 |
Loans and Leases Receivable, Gross, Total | 577,886,000 | 556,053,000 |
Non-accruing loans | $ 3,415,000 | 3,723,000 |
Percentage of loan balance to Major Franchises | 90.00% |  |
Percentage of restaurants loan balance accounted to franchised fast food | 54.00% |  |
Percentage of loan balance accounted to dine in restaurant | 46.00% |  |
Lease term for Contract | 12 months |  |
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest | $ 3,400,000 | 3,700,000 |
Financing Receivable, Troubled Debt Restructuring | 100,000 | 100,000 |
Impaired loans with no related allowance recorded, carrying amount | 3,680,000 | 2,861,000 |
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans | 45,000 | 41,000 |
Interest Income Recorded | 27,000 | 147,000 |
Financing Receivable, Restructuring Recorded Investment With Nonaccrual Status | 12,000 | 16,000 |
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 | $ 6,423,000 | $ 5,762,000 |
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 | 500,000 |  |
Loans, allowance for loan losses | 1,000 | 1,000 |
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 | $ 500,000 |  |
Minimum [Member] | ALC [Member] |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest |  | 50,000 |
Paycheck Protection Program [Member] |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |
Loan, fixed interest rate | 1.00% |  |
Loan, aggregate principal balance | $ 13,800,000 |  |
Number of loans to small businesses | Loan | 158 |  |
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% |  |
Paycheck Protection Program [Member] | Two Year Term Loan [Member] |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |
Loan, aggregate principal balance | $ 13,700,000 |  |
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 | $ 100,000 |  |
Loan payment term | five-year |  |
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |
Loans and Leases Receivable, Gross, Total | $ 1,965,000 |  |
Financial Asset Acquired With Credit Deterioration [Member] |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |
Loans and Leases Receivable, Gross, Total | 167,000 |  |
Non-accruing loans | 200,000 | 200,000 |
Impaired loans with no related allowance recorded, carrying amount | 200,000 | 200,000 |
Financial Asset Acquired With Credit Deterioration [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |
Loans and Leases Receivable, Gross, Total | 200,000 | 200,000 |
Financial Asset Acquired With Credit Deterioration [Member] | Substandard [Member] |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |
Loans and Leases Receivable, Gross, Total | $ 200,000 | $ 200,000 |
Real Estate [Member] |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |
Percentage of Loan Portfolio | 57.80% | 62.80% |

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