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Fair Value of Financial Instruments (Narrative) (Details) - USD ($) | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Jun. 30, 2023 | Jan. 01, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |
Gains or losses included in earnings attributable to the change in realized/unrealized gains or losses related to the assets | $ 0 | $ 0 | $ 0 | $ 0 |  |  |
Credit loss expense - loans |  | $ (108,000) |  | $ 97,000 |  |  |
Nonaccrual loans |  |  |  |  | $ 3,495,000 |  |
Allowance for loan losses | (17,146,000) |  | (17,146,000) |  |  | $ (16,905,000) | $ (16,702,000)
Loans | 1,380,019,000 |  | 1,380,019,000 |  |  |  |
Impaired Loans with No Specific Allowance: Recorded Investment | 2,314,000 |  | 2,314,000 |  |  |  |
Financing receivables minimum benchmark for evaluation for specific reserves | 100,000 |  | 100,000 |  |  |  |
Financing receivable individually evaluated with no allowance carrying value | $ 2,300,000 |  | $ 2,300,000 |  |  |  |
Partial Charge Off [Member] |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |
Nonaccrual loans |  |  |  |  | 100,000 |  |
Troubled Debt Restructuring [Member] |  |  |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |  |
Credit loss expense - loans |  |  |  |  | 1,300,000 |  |
Allowance for loan losses |  |  |  |  | (400,000) |  |
Impaired Loans with Specific Allowance: Recorded Investment |  |  |  |  | 1,000,000.0 |  |
Impaired Loans with Specific Allowance: Related Allowance |  |  |  |  | $ 64,700 |  |

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- Definition Financing receivables minimum benchmark for evaluation for specific reserves. + References No definition available. + Details
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- Definition Amount of allowance for credit losses related to impaired financing receivable excluding accrued interest. + References No definition available. + Details
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- Definition Amount of investment in impaired financing receivables excluding accrued interest for which there is no related allowance for credit losses. + References No definition available. + Details
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- Definition Amount of investment in impaired financing receivables excluding accrued interest for which there is a related allowance for credit losses. + References No definition available. + Details
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- Definition For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482907/825-10-50-30 + Details
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