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Loans and Allowance for Credit Losses on Loans - Schedule of Loans Outstanding and Aging Analysis (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | $ 2,086,942,000 |  | $ 2,086,942,000 |  | $ 2,092,546,000
Loans past due more than 90 days still accruing | 0 |  | 0 |  | 0
Financing receivable, nonaccrual, earning interest on cash basis | 0 |  | 0 |  | 0
Nonaccrual interest income reversal | 131,000 | $ 39,000 | 158,000 | $ 47,000 |
Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 2,086,942,000 |  | 2,086,942,000 |  | 2,092,546,000
Non-accrual loans | 5,672,000 |  | 5,672,000 |  | 2,432,000
Non-accrual loans with no allowance | 5,672,000 |  | 5,672,000 |  | 2,432,000
Total past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 7,309,000 |  | 7,309,000 |  | 1,342,000
30-59 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 2,215,000 |  | 2,215,000 |  | 420,000
60-89 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 1,098,000 |  | 1,098,000 |  | 244,000
90 days or more past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 3,996,000 |  | 3,996,000 |  | 678,000
Current | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 2,079,633,000 |  | 2,079,633,000 |  | 2,091,204,000
Commercial loans | Commercial and industrial |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 174,096,000 |  | 174,096,000 |  | 173,547,000
Commercial loans | Commercial and industrial | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 174,096,000 |  | 174,096,000 |  | 173,547,000
Non-accrual loans | 0 |  | 0 |  | 0
Non-accrual loans with no allowance | 0 |  | 0 |  | 0
Commercial loans | Commercial and industrial | Total past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 1,321,000 |  | 1,321,000 |  | 267,000
Commercial loans | Commercial and industrial | 30-59 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 1,321,000 |  | 1,321,000 |  | 3,000
Commercial loans | Commercial and industrial | 60-89 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 0
Commercial loans | Commercial and industrial | 90 days or more past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 264,000
Commercial loans | Commercial and industrial | Current | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 172,775,000 |  | 172,775,000 |  | 173,280,000
Commercial real estate loans | Commercial owner-occupied |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 346,307,000 |  | 346,307,000 |  | 354,877,000
Commercial real estate loans | Commercial owner-occupied | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 346,307,000 |  | 346,307,000 |  | 354,877,000
Non-accrual loans | 4,281,000 |  | 4,281,000 |  | 1,563,000
Non-accrual loans with no allowance | 4,281,000 |  | 4,281,000 |  | 1,563,000
Commercial real estate loans | Commercial owner-occupied | Total past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 3,992,000 |  | 3,992,000 |  | 0
Commercial real estate loans | Commercial owner-occupied | 30-59 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 0
Commercial real estate loans | Commercial owner-occupied | 60-89 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 0
Commercial real estate loans | Commercial owner-occupied | 90 days or more past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 3,992,000 |  | 3,992,000 |  | 0
Commercial real estate loans | Commercial owner-occupied | Current | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 342,315,000 |  | 342,315,000 |  | 354,877,000
Commercial real estate loans | Commercial non-owner occupied |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 1,190,813,000 |  | 1,190,813,000 |  | 1,191,889,000
Commercial real estate loans | Commercial non-owner occupied | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 1,190,813,000 |  | 1,190,813,000 |  | 1,191,889,000
Non-accrual loans | 901,000 |  | 901,000 |  | 0
Non-accrual loans with no allowance | 901,000 |  | 901,000 |  | 0
Commercial real estate loans | Commercial non-owner occupied | Total past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 1,698,000 |  | 1,698,000 |  | 0
Commercial real estate loans | Commercial non-owner occupied | 30-59 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 797,000 |  | 797,000 |  | 0
Commercial real estate loans | Commercial non-owner occupied | 60-89 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 901,000 |  | 901,000 |  | 0
Commercial real estate loans | Commercial non-owner occupied | 90 days or more past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 0
Commercial real estate loans | Commercial non-owner occupied | Current | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 1,189,115,000 |  | 1,189,115,000 |  | 1,191,889,000
Commercial real estate loans | Construction |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 109,305,000 |  | 109,305,000 |  | 114,373,000
Commercial real estate loans | Construction | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 109,305,000 |  | 109,305,000 |  | 114,373,000
Non-accrual loans | 0 |  | 0 |  | 0
Non-accrual loans with no allowance | 0 |  | 0 |  | 0
Commercial real estate loans | Construction | Total past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 0
Commercial real estate loans | Construction | 30-59 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 0
Commercial real estate loans | Construction | 60-89 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 0
Commercial real estate loans | Construction | 90 days or more past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 0
Commercial real estate loans | Construction | Current | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 109,305,000 |  | 109,305,000 |  | 114,373,000
Residential loans | Home equity |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 83,267,000 |  | 83,267,000 |  | 88,748,000
Residential loans | Home equity | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 83,267,000 |  | 83,267,000 |  | 88,748,000
Non-accrual loans | 490,000 |  | 490,000 |  | 778,000
Non-accrual loans with no allowance | 490,000 |  | 490,000 |  | 778,000
Residential loans | Home equity | Total past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 200,000 |  | 200,000 |  | 977,000
Residential loans | Home equity | 30-59 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 319,000
Residential loans | Home equity | 60-89 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 196,000 |  | 196,000 |  | 244,000
Residential loans | Home equity | 90 days or more past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 4,000 |  | 4,000 |  | 414,000
Residential loans | Home equity | Current | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 83,067,000 |  | 83,067,000 |  | 87,771,000
Residential loans | Other residential |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 116,674,000 |  | 116,674,000 |  | 112,123,000
Residential loans | Other residential | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 116,674,000 |  | 116,674,000 |  | 112,123,000
Non-accrual loans | 0 |  | 0 |  | 0
Non-accrual loans with no allowance | 0 |  | 0 |  | 0
Residential loans | Other residential | Total past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 93,000
Residential loans | Other residential | 30-59 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 93,000
Residential loans | Other residential | 60-89 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 0
Residential loans | Other residential | 90 days or more past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 0
Residential loans | Other residential | Current | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 116,674,000 |  | 116,674,000 |  | 112,030,000
Consumer loans | Installment and other consumer loans |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 66,480,000 |  | 66,480,000 |  | 56,989,000
Consumer loans | Installment and other consumer loans | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 66,480,000 |  | 66,480,000 |  | 56,989,000
Non-accrual loans | 0 |  | 0 |  | 91,000
Non-accrual loans with no allowance | 0 |  | 0 |  | 91,000
Consumer loans | Installment and other consumer loans | Total past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 98,000 |  | 98,000 |  | 5,000
Consumer loans | Installment and other consumer loans | 30-59 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 97,000 |  | 97,000 |  | 5,000
Consumer loans | Installment and other consumer loans | 60-89 days past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 1,000 |  | 1,000 |  | 0
Consumer loans | Installment and other consumer loans | 90 days or more past due | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | 0 |  | 0 |  | 0
Consumer loans | Installment and other consumer loans | Current | Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans, at amortized cost | $ 66,382,000 |  | $ 66,382,000 |  | $ 56,984,000

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