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Loans and Allowance for Credit Losses on Loans - Schedule of Collateral-Dependent Non-Accrual Loans (Details) - USD ($) | Sep. 30, 2023 | Jun. 30, 2023 | Dec. 31, 2022 | Sep. 30, 2022 | Jun. 30, 2022 | Dec. 31, 2021
--- | --- | --- | --- | --- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Allowance for credit losses | $ 24,260,000 | $ 23,832,000 | $ 22,983,000 | $ 22,963,000 | $ 22,539,000 | $ 23,023,000
Nonaccrual collateral dependent loans in process of foreclosure | $ 0 |  | $ 0 |  |  |
Weighted average ratio of loans value to collateral dependent loans value | 61.00% |  | 42.00% |  |  |
Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | $ 5,672,000 |  | $ 2,432,000 |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Commercial Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 5,182,000 |  | 1,563,000 |  |  |
Residential Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 490,000 |  | 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 | 2,530,000 | 2,589,000 | 2,487,000 | 2,536,000 | 2,617,000 | 2,776,000
Commercial real estate loans | Commercial owner-occupied | Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 4,281,000 |  | 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 | 4,281,000 |  | 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 | 13,624,000 | 13,201,000 | 12,676,000 | 12,738,000 | 12,439,000 |
Commercial real estate loans | Commercial non-owner occupied | Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 901,000 |  |  |  |  |
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 | 901,000 |  |  |  |  |
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 | 565,000 | 561,000 | 558,000 | 542,000 | 530,000 | 595,000
Residential loans | Home equity | Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 490,000 |  | 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 | 490,000 |  | 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 | $ 605,000 | $ 599,000 | $ 595,000 | $ 590,000 | $ 585,000 | $ 644,000

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