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Loans and Allowance for Credit Losses on Loans - Schedule of Collateral-Dependent Non-Accrual Loans (Details) - USD ($) | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 31, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | --- | --- | --- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Allowance for credit losses | $ 23,832,000 | $ 23,330,000 | $ 22,983,000 | $ 22,539,000 | $ 22,547,000 | $ 23,023,000
Weighted average ratio of loans value to collateral dependent loans value | 40.00% |  | 42.00% |  |  |
Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | $ 2,112,000 |  | $ 2,432,000 |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Commercial Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 1,363,000 |  | 1,563,000 |  |  |
Residential Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 749,000 |  | 778,000 |  |  |
Other |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 0 |  | 91,000 |  |  |
Commercial real estate loans | Commercial owner-occupied |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Allowance for credit losses | 2,589,000 | 2,640,000 | 2,487,000 | 2,617,000 | 2,622,000 | 2,776,000
Commercial real estate loans | Commercial owner-occupied | Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 457,000 |  | 1,563,000 |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Commercial real estate loans | Commercial owner-occupied | Commercial Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 457,000 |  | 1,563,000 |  |  |
Commercial real estate loans | Commercial owner-occupied | Residential Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 0 |  | 0 |  |  |
Commercial real estate loans | Commercial owner-occupied | Other |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 0 |  | 0 |  |  |
Commercial real estate loans | Commercial non-owner occupied |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Allowance for credit losses | 13,201,000 | 12,701,000 | 12,676,000 | 12,439,000 | 12,301,000 |
Commercial real estate loans | Commercial non-owner occupied | Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 906,000 |  |  |  |  |
Allowance for credit losses | 0 |  |  |  |  |
Commercial real estate loans | Commercial non-owner occupied | Commercial Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 906,000 |  |  |  |  |
Commercial real estate loans | Commercial non-owner occupied | Residential Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 0 |  |  |  |  |
Commercial real estate loans | Commercial non-owner occupied | Other |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 0 |  |  |  |  |
Commercial real estate loans | Installment and other consumer loans | Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans |  |  | 91,000 |  |  |
Allowance for credit losses |  |  | 0 |  |  |
Commercial real estate loans | Installment and other consumer loans | Commercial Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans |  |  | 0 |  |  |
Commercial real estate loans | Installment and other consumer loans | Residential Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans |  |  | 0 |  |  |
Commercial real estate loans | Installment and other consumer loans | Other |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans |  |  | 91,000 |  |  |
Residential loans | Home equity |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Allowance for credit losses | 561,000 | 538,000 | 558,000 | 530,000 | 549,000 | 595,000
Residential loans | Home equity | Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 749,000 |  | 778,000 |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Residential loans | Home equity | Commercial Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 0 |  | 0 |  |  |
Residential loans | Home equity | Residential Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 749,000 |  | 778,000 |  |  |
Residential loans | Home equity | Other |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 0 |  | 0 |  |  |
Residential loans | Other residential |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Allowance for credit losses | 599,000 | $ 577,000 | 595,000 | $ 585,000 | $ 628,000 | $ 644,000
Residential loans | Other residential | Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Nonaccrual collateral dependent loans in process of foreclosure | $ 0 |  | $ 0 |  |  |

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