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Nature of Operations and Summary of Significant Accounting Policies (Narrative) (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2023 USD ($) Location shares | Dec. 31, 2022 USD ($) shares | Dec. 31, 2021 USD ($)
Accounting Policies [Abstract] |  |  |
Other Real Estate, Foreclosed Assets, and Repossessed Assets | $ 406 | $ 439 |
Number of location of banking operations | Location | 31 |  |
Period for federal fund sold | 1 day |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Unpaid principal balance of mortgages serviced for others | $ 248,756 | 264,206 |
Capitalized mortgage loans on real estate carrying amount | 2,422 | 2,559 |
Corporation recorded servicing fee revenue | 630 | 669 | $ 747
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |
Present value of the post retirement benefits payable | 2,515 | 2,905 |
Periodic policy maintenance costs | $ 173 | $ 61 | $ 33
Director [Member] |  |  |
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |
Eligible shares, total | shares | 154,119 | 207,840 |
Common stock, shares held in Rabbi Trust | shares | 150,581 | 154,879 |
Minimum [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful lives of the related assets | 3 years |  |
Maximum [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful lives of the related assets | 40 years |  |
Loans |  |  |
Condensed Balance Sheet Statements, Captions [Line Items] |  |  |
Interest Receivable | $ 5,920 |  |
Debt Securities [Member] |  |  |
Condensed Balance Sheet Statements, Captions [Line Items] |  |  |
Interest Receivable | $ 2,247 |  |

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