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Loans and Allowance for Credit Losses - Loans Outstanding and Aging Analysis (Details) | 12 Months Ended
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Dec. 31, 2022 USD ($) loan | Dec. 31, 2021 USD ($) loan | Dec. 31, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | $ 2,092,546,000 | $ 2,255,645,000 |
Non-accrual loans | 2,432,000 | 8,376,000 |
Non-accrual loans with no allowance | $ 2,432,000 | $ 8,376,000 |
Number of loans past due more than 90 days still accruing | loan | 0 | 0 |
Nonaccrual loans earning interest on cash basis | $ 0 | $ 0 |
Nonaccrual interest income | 0 | 0 | $ 0
Accrued interest writeoff | 48,000 | 0 |
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 2,092,546,000 | 2,255,645,000 |
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 | 1,342,000 | 2,314,000 |
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 | 420,000 | 1,536,000 |
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 | 244,000 | 461,000 |
90 days or more past due 1 | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 678,000 | 317,000 |
Current | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 2,091,204,000 | 2,253,331,000 |
Commercial | Commercial and industrial |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 173,547,000 | 301,602,000 |
Non-accrual loans | 0 | 0 |
Non-accrual loans with no allowance | 0 | 0 |
Commercial | Commercial and industrial | Small Business Administration Paycheck Protection Program |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 3,500,000 | 111,200,000 | $ 444,100,000
Commercial | 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 | 173,547,000 | 301,602,000 |
Commercial | 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 | 267,000 | 625,000 |
Commercial | 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 | 3,000 | 2,000 |
Commercial | 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 | 394,000 |
Commercial | Commercial and industrial | 90 days or more past due 1 | Small Business Administration Paycheck Protection Program |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 264,000 | 229,000 |
Commercial | Commercial and industrial | 90 days or more past due 1 | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 264,000 | 229,000 |
Commercial | 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 | 173,280,000 | 300,977,000 |
Commercial real estate | Commercial owner-occupied |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 354,877,000 | 392,345,000 |
Non-accrual loans | 1,563,000 | 7,269,000 |
Non-accrual loans with no allowance | 1,563,000 | 7,269,000 |
Commercial real estate | 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 | 354,877,000 | 392,345,000 |
Commercial real estate | 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 | 0 | 0 |
Commercial real estate | 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 |
Commercial real estate | 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 |
Commercial real estate | Commercial owner-occupied | 90 days or more past due 1 | 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 | 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 | 354,877,000 | 392,345,000 |
Commercial real estate | Commercial investor-owned |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 1,191,889,000 | 1,189,021,000 |
Non-accrual loans | 0 | 694,000 |
Non-accrual loans with no allowance | 0 | 694,000 |
Commercial real estate | Commercial investor-owned | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 1,191,889,000 | 1,189,021,000 |
Commercial real estate | Commercial investor-owned | 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 | Commercial investor-owned | 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 | Commercial investor-owned | 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 | Commercial investor-owned | 90 days or more past due 1 | 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 | Commercial investor-owned | Current | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 1,191,889,000 | 1,189,021,000 |
Commercial real estate | Construction |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 114,373,000 | 119,840,000 |
Non-accrual loans | 0 | 0 |
Non-accrual loans with no allowance | 0 | 0 |
Commercial real estate | Construction | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 114,373,000 | 119,840,000 |
Commercial real estate | 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 | 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 | 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 | Construction | 90 days or more past due 1 | 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 | Construction | Current | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 114,373,000 | 119,840,000 |
Residential loans | Home equity |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 88,748,000 | 88,746,000 |
Non-accrual loans | 778,000 | 413,000 |
Non-accrual loans with no allowance | 778,000 | 413,000 |
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 | 88,748,000 | 88,746,000 |
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 | 977,000 | 653,000 |
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 | 319,000 | 498,000 |
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 | 244,000 | 67,000 |
Residential loans | Home equity | 90 days or more past due 1 | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 414,000 | 88,000 |
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 | 87,771,000 | 88,093,000 |
Residential loans | Other residential |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 112,123,000 | 114,558,000 |
Non-accrual loans | 0 | 0 |
Non-accrual loans with no allowance | 0 | 0 |
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 | 112,123,000 | 114,558,000 |
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 | 93,000 | 0 |
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 | 93,000 | 0 |
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 1 | 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 | 112,030,000 | 114,558,000 |
Consumer loans | Installment and other consumer loans |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 56,989,000 | 49,533,000 |
Non-accrual loans | 91,000 | 0 |
Non-accrual loans with no allowance | 91,000 | 0 |
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 | 56,989,000 | 49,533,000 |
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 | 5,000 | 1,036,000 |
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 | 5,000 | 1,036,000 |
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 | 0 | 0 |
Consumer loans | Installment and other consumer loans | 90 days or more past due 1 | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans, at amortized cost | 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 | $ 56,984,000 | $ 48,497,000 |

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