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Loans and Allowance for Credit Losses on Loans - Loans Outstanding and Aging Analysis (Details) | 12 Months Ended
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Dec. 31, 2024 USD ($) loan | Dec. 31, 2023 USD ($) loan | Dec. 31, 2022 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | $ 2,083,256,000 | $ 2,073,720,000 |
Number of loans past due more than 90 days still accruing | loan | 0 | 0 |
Financing receivable, nonaccrual, earning interest on cash basis | $ 0 | $ 0 |
Nonaccrual interest income | 0 | 0 | $ 0
Nonaccrual interest income reversal | 530,000 | 206,000 | $ 48,000
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 2,083,256,000 | 2,073,720,000 |
Non-accrual loans | 33,881,000 | 7,992,000 |
Non-accrual loans with no allowance | 2,993,000 | 3,091,000 |
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 | 16,938,000 | 7,664,000 |
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 | 2,282,000 | 3,930,000 |
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 | 752,000 | 2,274,000 |
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 | 13,904,000 | 1,460,000 |
Current | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 2,066,318,000 | 2,066,056,000 |
Commercial and industrial | Commercial and industrial |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 152,263,000 | 153,750,000 |
Commercial and industrial | 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 | 152,263,000 | 153,750,000 |
Non-accrual loans | 2,845,000 | 4,008,000 |
Non-accrual loans with no allowance | 0 | 1,311,000 |
Commercial and industrial | 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 | 2,996,000 | 4,371,000 |
Commercial and industrial | 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 | 203,000 | 2,991,000 |
Commercial and industrial | 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 | 69,000 |
Commercial and industrial | 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 | 2,793,000 | 1,311,000 |
Commercial and industrial | 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 | 149,267,000 | 149,379,000 |
Commercial real estate loans | Commercial owner-occupied |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 321,962,000 | 333,181,000 |
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 | 321,962,000 | 333,181,000 |
Non-accrual loans | 1,537,000 | 434,000 |
Non-accrual loans with no allowance | 1,537,000 | 434,000 |
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 | 880,000 | 767,000 |
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 | 208,000 | 618,000 |
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 | 559,000 | 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 | 113,000 | 149,000 |
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 | 321,082,000 | 332,414,000 |
Commercial real estate loans | Commercial real estate, non-owner occupied |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 1,273,596,000 | 1,219,385,000 |
Commercial real estate loans | Commercial real estate, 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 | 1,273,596,000 | 1,219,385,000 |
Non-accrual loans | 28,525,000 | 3,081,000 |
Non-accrual loans with no allowance | 497,000 | 877,000 |
Commercial real estate loans | Commercial real estate, 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 | 11,460,000 | 2,204,000 |
Commercial real estate loans | Commercial real estate, 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 | 718,000 | 0 |
Commercial real estate loans | Commercial real estate, 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 | 0 | 2,204,000 |
Commercial real estate loans | Commercial real estate, 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 | 10,742,000 | 0 |
Commercial real estate loans | Commercial real estate, 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 | 1,262,136,000 | 1,217,181,000 |
Commercial real estate loans | Construction |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 36,970,000 | 99,164,000 |
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 | 36,970,000 | 99,164,000 |
Non-accrual loans | 0 | 0 |
Non-accrual loans with no allowance | 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 |
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 |
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 |
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 |
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 | 36,970,000 | 99,164,000 |
Residential loans | Home equity |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 88,325,000 | 82,087,000 |
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 | 88,325,000 | 82,087,000 |
Non-accrual loans | 752,000 | 469,000 |
Non-accrual loans with no allowance | 752,000 | 469,000 |
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 | 1,172,000 | 43,000 |
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 | 738,000 | 43,000 |
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 | 186,000 | 0 |
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 | 248,000 | 0 |
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 | 87,153,000 | 82,044,000 |
Residential loans | Other residential |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 143,207,000 | 118,508,000 |
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 | 143,207,000 | 118,508,000 |
Non-accrual loans | 0 | 0 |
Non-accrual loans with no allowance | 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 | 83,000 |
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 | 83,000 |
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 |
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 |
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 | 143,207,000 | 118,425,000 |
Installment and other consumer | Installment and other consumer loans |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 66,933,000 | 67,645,000 |
Installment and other consumer | 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 | 66,933,000 | 67,645,000 |
Non-accrual loans | 222,000 | 0 |
Non-accrual loans with no allowance | 207,000 | 0 |
Installment and other consumer | 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 | 430,000 | 196,000 |
Installment and other consumer | 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 | 415,000 | 195,000 |
Installment and other consumer | 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 | 7,000 | 1,000 |
Installment and other consumer | 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 | 8,000 | 0 |
Installment and other consumer | 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 | $ 66,503,000 | $ 67,449,000 |

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