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Loans and Allowance for Credit Losses on Loans - Allocation of the Allowance for Credit Losses on Loans (Details) - USD ($) $ in Thousands | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 31, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | --- | --- | --- | --- | ---
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | $ 23,832 | $ 23,330 | $ 22,983 | $ 22,539 | $ 22,547 | $ 23,023
Modeled expected credit losses |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 11,718 |  | 12,651 |  |  |
Qualitative adjustments |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 12,093 |  | 10,323 |  |  |
Specific allocations |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 21 |  | 9 |  |  |
Commercial loans | Commercial and industrial |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 1,831 | 1,941 | 1,794 | 1,699 | 1,784 | 1,709
Commercial loans | Commercial and industrial | Modeled expected credit losses |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 1,100 |  | 1,079 |  |  |
Commercial loans | Commercial and industrial | Qualitative adjustments |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 711 |  | 706 |  |  |
Commercial loans | Commercial and industrial | Specific allocations |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 20 |  | 9 |  |  |
Commercial real estate loans | Commercial owner-occupied |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 2,589 | 2,640 | 2,487 | 2,617 | 2,622 | 2,776
Commercial real estate loans | Commercial owner-occupied | Modeled expected credit losses |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 1,329 |  | 1,497 |  |  |
Commercial real estate loans | Commercial owner-occupied | Qualitative adjustments |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 1,260 |  | 990 |  |  |
Commercial real estate loans | Commercial owner-occupied | Specific allocations |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Commercial real estate loans | Commercial non-owner occupied |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 13,201 | 12,701 | 12,676 | 12,439 | 12,301 |
Commercial real estate loans | Commercial non-owner occupied | Modeled expected credit losses |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 7,441 |  | 7,937 |  |  |
Commercial real estate loans | Commercial non-owner occupied | Qualitative adjustments |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 5,760 |  | 4,739 |  |  |
Commercial real estate loans | Commercial non-owner occupied | Specific allocations |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Commercial real estate loans | Construction |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 1,942 | 2,019 | 1,937 | 1,737 | 1,717 | 1,653
Commercial real estate loans | Construction | Modeled expected credit losses |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 195 |  | 453 |  |  |
Commercial real estate loans | Construction | Qualitative adjustments |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 1,747 |  | 1,484 |  |  |
Commercial real estate loans | Construction | Specific allocations |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Residential loans | Home equity |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 561 | 538 | 558 | 530 | 549 | 595
Residential loans | Home equity | Modeled expected credit losses |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 486 |  | 504 |  |  |
Residential loans | Home equity | Qualitative adjustments |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 75 |  | 54 |  |  |
Residential loans | Home equity | Specific allocations |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Residential loans | Other residential |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 599 | 577 | 595 | 585 | 628 | 644
Residential loans | Other residential | Modeled expected credit losses |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 558 |  | 571 |  |  |
Residential loans | Other residential | Qualitative adjustments |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 40 |  | 24 |  |  |
Residential loans | Other residential | Specific allocations |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 1 |  | 0 |  |  |
Consumer loans | Installment and other consumer loans |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 940 | 882 | 868 | 733 | 641 | 621
Consumer loans | Installment and other consumer loans | Modeled expected credit losses |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 609 |  | 610 |  |  |
Consumer loans | Installment and other consumer loans | Qualitative adjustments |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 331 |  | 258 |  |  |
Consumer loans | Installment and other consumer loans | Specific allocations |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Unallocated |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 2,169 | $ 2,032 | 2,068 | $ 2,199 | $ 2,305 | $ 2,286
Unallocated | Modeled expected credit losses |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Unallocated | Qualitative adjustments |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | 2,169 |  | 2,068 |  |  |
Unallocated | Specific allocations |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Allowance for credit losses | $ 0 |  | $ 0 |  |  |

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