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Loans and Allowance for Credit Losses on Loans - Outstanding and Aging Analysis (Details) | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2022 USD ($) loan | Jun. 30, 2021 USD ($) | Jun. 30, 2022 USD ($) loan | Jun. 30, 2021 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | $ 2,162,632,000 |  | $ 2,162,632,000 |  | $ 2,255,645,000 |
Loans past due more than 90 days still accruing | 0 |  | 0 |  | 0 |
Financing receivable, nonaccrual, earning interest on cash basis | 0 |  | 0 |  | 0 |
Financing receivable, nonaccrual, interest income | 0 | $ 0 | $ 0 | $ 0 |  |
Financing receivable, number of loans placed on nonaccrual status | loan |  |  | 3 |  |  |
Financing receivable, nonaccrual, amortized cost | $ 397,000 |  | $ 397,000 |  |  |
Financing receivable, number of loans accrued interest written off | loan | 1 |  |  |  |  |
Financing receivable, accrued interest, writeoff | $ 16,000 |  | 8,000 |  |  |
Commercial loans | Commercial and industrial |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 213,122,000 |  | 213,122,000 |  | 301,602,000 |
Commercial loans | Commercial and industrial | SBA PPP |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 17,000,000 |  | 17,000,000 |  | 111,200,000 | $ 444,100,000
Commercial real estate loans | Commercial owner-occupied |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 382,897,000 |  | 382,897,000 |  | 392,345,000 |
Commercial real estate loans | Commercial investor-owned |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 1,190,419,000 |  | 1,190,419,000 |  | 1,189,021,000 |
Commercial real estate loans | Construction |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 118,147,000 |  | 118,147,000 |  | 119,840,000 |
Residential loans | Home equity |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 90,629,000 |  | 90,629,000 |  | 88,746,000 |
Residential loans | Other residential |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 113,361,000 |  | 113,361,000 |  | 114,558,000 |
Consumer loans | Installment and other consumer loans |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 54,057,000 |  | 54,057,000 |  | 49,533,000 |
Financial asset, other than financial asset acquired with credit deterioration |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 2,162,632,000 |  | 2,162,632,000 |  | 2,255,645,000 |
Non-accrual loans | 8,018,000 |  | 8,018,000 |  | 8,376,000 |
Non-accrual loans with no allowance | 8,018,000 |  | 8,018,000 |  | 8,376,000 |
Financial asset, other than financial asset acquired with credit deterioration | Total past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 3,409,000 |  | 3,409,000 |  | 2,314,000 |
Financial asset, other than financial asset acquired with credit deterioration | 30-59 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 1,991,000 |  | 1,991,000 |  | 1,536,000 |
Financial asset, other than financial asset acquired with credit deterioration | 60-89 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 1,162,000 |  | 1,162,000 |  | 461,000 |
Financial asset, other than financial asset acquired with credit deterioration | 90 days or more past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 256,000 |  | 256,000 |  | 317,000 |
Financial asset, other than financial asset acquired with credit deterioration | Current |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 2,159,223,000 |  | 2,159,223,000 |  | 2,253,331,000 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial loans | Commercial and industrial |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 213,122,000 |  | 213,122,000 |  | 301,602,000 |
Non-accrual loans | 0 |  | 0 |  | 0 |
Non-accrual loans with no allowance | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial loans | Commercial and industrial | Total past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 1,856,000 |  | 1,856,000 |  | 625,000 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial loans | Commercial and industrial | 30-59 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 1,065,000 |  | 1,065,000 |  | 2,000 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial loans | Commercial and industrial | 60-89 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 589,000 |  | 589,000 |  | 394,000 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial loans | Commercial and industrial | 90 days or more past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 202,000 |  | 202,000 |  | 229,000 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial loans | Commercial and industrial | Current |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 211,266,000 |  | 211,266,000 |  | 300,977,000 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Commercial owner-occupied |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 382,897,000 |  | 382,897,000 |  | 392,345,000 |
Non-accrual loans | 7,564,000 |  | 7,564,000 |  | 7,269,000 |
Non-accrual loans with no allowance | 7,564,000 |  | 7,564,000 |  | 7,269,000 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Commercial owner-occupied | Total past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 1,205,000 |  | 1,205,000 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Commercial owner-occupied | 30-59 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 660,000 |  | 660,000 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Commercial owner-occupied | 60-89 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 545,000 |  | 545,000 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Commercial owner-occupied | 90 days or more past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Commercial owner-occupied | Current |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 381,692,000 |  | 381,692,000 |  | 392,345,000 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Commercial investor-owned |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 1,190,419,000 |  | 1,190,419,000 |  | 1,189,021,000 |
Non-accrual loans | 0 |  | 0 |  | 694,000 |
Non-accrual loans with no allowance | 0 |  | 0 |  | 694,000 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Commercial investor-owned | Total past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Commercial investor-owned | 30-59 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Commercial investor-owned | 60-89 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Commercial investor-owned | 90 days or more past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Commercial investor-owned | Current |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 1,190,419,000 |  | 1,190,419,000 |  | 1,189,021,000 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Construction |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 118,147,000 |  | 118,147,000 |  | 119,840,000 |
Non-accrual loans | 0 |  | 0 |  | 0 |
Non-accrual loans with no allowance | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Construction | Total past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Construction | 30-59 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Construction | 60-89 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Construction | 90 days or more past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Commercial real estate loans | Construction | Current |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 118,147,000 |  | 118,147,000 |  | 119,840,000 |
Financial asset, other than financial asset acquired with credit deterioration | Residential loans | Home equity |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 90,629,000 |  | 90,629,000 |  | 88,746,000 |
Non-accrual loans | 454,000 |  | 454,000 |  | 413,000 |
Non-accrual loans with no allowance | 454,000 |  | 454,000 |  | 413,000 |
Financial asset, other than financial asset acquired with credit deterioration | Residential loans | Home equity | Total past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 154,000 |  | 154,000 |  | 653,000 |
Financial asset, other than financial asset acquired with credit deterioration | Residential loans | Home equity | 30-59 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 100,000 |  | 100,000 |  | 498,000 |
Financial asset, other than financial asset acquired with credit deterioration | Residential loans | Home equity | 60-89 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 67,000 |
Financial asset, other than financial asset acquired with credit deterioration | Residential loans | Home equity | 90 days or more past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 54,000 |  | 54,000 |  | 88,000 |
Financial asset, other than financial asset acquired with credit deterioration | Residential loans | Home equity | Current |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 90,475,000 |  | 90,475,000 |  | 88,093,000 |
Financial asset, other than financial asset acquired with credit deterioration | Residential loans | Other residential |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 113,361,000 |  | 113,361,000 |  | 114,558,000 |
Non-accrual loans | 0 |  | 0 |  | 0 |
Non-accrual loans with no allowance | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Residential loans | Other residential | Total past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Residential loans | Other residential | 30-59 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Residential loans | Other residential | 60-89 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Residential loans | Other residential | 90 days or more past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Residential loans | Other residential | Current |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 113,361,000 |  | 113,361,000 |  | 114,558,000 |
Financial asset, other than financial asset acquired with credit deterioration | Consumer loans | Installment and other consumer loans |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 54,057,000 |  | 54,057,000 |  | 49,533,000 |
Non-accrual loans | 0 |  | 0 |  | 0 |
Non-accrual loans with no allowance | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Consumer loans | Installment and other consumer loans | Total past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 194,000 |  | 194,000 |  | 1,036,000 |
Financial asset, other than financial asset acquired with credit deterioration | Consumer loans | Installment and other consumer loans | 30-59 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 166,000 |  | 166,000 |  | 1,036,000 |
Financial asset, other than financial asset acquired with credit deterioration | Consumer loans | Installment and other consumer loans | 60-89 days past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 28,000 |  | 28,000 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Consumer loans | Installment and other consumer loans | 90 days or more past due |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | 0 |  | 0 |  | 0 |
Financial asset, other than financial asset acquired with credit deterioration | Consumer loans | Installment and other consumer loans | Current |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans at amortized cost | $ 53,863,000 |  | $ 53,863,000 |  | $ 48,497,000 |

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