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Basis of Presentation and Summary of Significant Accounting Policies (Narrative) (Details) |  |  | 1 Months Ended | 3 Months Ended | 4 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 07, 2020 USD ($) | Mar. 27, 2020 USD ($) | Oct. 31, 2020 USD ($) Branch | Dec. 31, 2020 USD ($) | Jul. 09, 2020 USD ($) | Sep. 30, 2020 USD ($) Segment | Nov. 06, 2020 shares | Dec. 31, 2019 USD ($)
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Retained earnings |  |  |  |  |  | $ 315,585,000 |  | $ 313,364,000
Number of identified portfolio segments | Segment |  |  |  |  |  | 6 |  |
Offering unsecured personal loans, percentage |  |  |  |  | 2.95% |  |  |
Scenario Forecast [Member] |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Severance costs and real estate related charges |  |  |  | $ 130,000 |  |  |  |
Subsequent Event [Member] |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Number of additional branches planned to close | Branch |  |  | 1 |  |  |  |  |
Expected annualized expense savings |  |  | $ 340,000 |  |  |  |  |
Stock repurchase program, number of shares authorized to be repurchased | shares |  |  |  |  |  |  | 801,879 |
Stock repurchase program, percentage of shares authorized to be repurchased |  |  |  |  |  |  | 5.00% |
Subsequent Event [Member] | Subordinated Notes due 2030 [Member] | Private Placement [Member] |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Debt instrument, aggregate principal amount | $ 35,000,000.0 |  |  |  |  |  |  |
Debt instrument, maturity date | Oct. 15, 2030 |  |  |  |  |  |  |
Debt instrument, payment terms | The Notes have a maturity date of October 15, 2030 and bear interest, payable semi-annually, at the rate of 4.375% per annum, until October 15, 2025. Commencing on that date, the interest rate will reset quarterly to an interest rate per annum equal to the then current three-month secured overnight financing rate (“SOFR”) plus 4.265%, payable quarterly until maturity. |  |  |  |  |  |  |
Debt instrument, interest rate | 4.375% |  |  |  |  |  |  |
Subsequent Event [Member] | Subordinated Notes due 2030 [Member] | Private Placement [Member] | Secured Overnight Financing Rate (“SOFR”) [Member] |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Debt instrument, percentage of basis spread on variable rate | 4.265% |  |  |  |  |  |  |
Maximum [Member] |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Certificate of deposit penalty fees for withdrawals |  |  |  |  | $ 20,000,000 |  |  |
Offering unsecured personal loans, amount |  |  |  |  | $ 5,000,000 |  |  |
Offering unsecured personal loans, period |  |  |  |  | 60 months |  |  |
CARES Act [Member] |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Estimated amount of relief fund |  | $ 2,200,000 |  |  |  |  |  |
ASU 2016-13 [Member] |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Retained earnings |  |  |  |  |  | $ (8,700,000) |  |
Increase in the allowance for credit losses on loans |  |  |  |  |  | 9,600,000 |  |
Increase (decrease) in deferred tax assets |  |  |  |  |  | 3,000,000.0 |  |
ASU 2016-13 [Member] | Held To Maturity Investment Securities [Member] |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Increase in the allowance for credit losses on loans |  |  |  |  |  | 14,000 |  |
ASU 2016-13 [Member] | Unfunded Commitments [Member] |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Increase in the allowance for credit losses on loans |  |  |  |  |  | $ 2,100,000 |  |

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