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Loans and Allowance for Credit Losses - Loans Outstanding and Aging Analysis (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 USD ($) loan | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Jun. 30, 2021 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | $ 2,255,645,000 | $ 2,088,556,000 |  |
Non-accrual loans | 8,376,000 | 9,233,000 |  |
Non-accrual loans with no allowance | 8,376,000 | 9,233,000 |  |
Loans past due more than 90 days still accruing |  | 0 |  |
Nonaccrual loans earning interest on cash basis | 0 | 0 |  |
Nonaccrual interest income | 0 | 0 | $ 0 |
Accrued interest writeoff | 0 | 36,000 |  |
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | 2,255,645,000 | 2,088,556,000 |  |
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 | 2,314,000 | 2,705,000 |  |
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 | 1,536,000 | 2,083,000 |  |
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 | 461,000 | 622,000 |  |
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 | 317,000 | 0 |  |
Current | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | 2,253,331,000 | 2,085,851,000 |  |
Commercial | Commercial and industrial |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | 301,602,000 | 498,408,000 |  |
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 | $ 111,200,000 | 291,600,000 |  | $ 444,100,000
Number of loans past due more than 90 days still accruing | loan | 2 |  |  |
Loans past due more than 90 days still accruing | $ 229,000 |  |  |
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 | 301,602,000 | 498,408,000 |  |
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 | 625,000 | 0 |  |
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 | 2,000 | 0 |  |
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 | 394,000 | 0 |  |
Commercial | 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 | 229,000 | 0 |  |
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 | 300,977,000 | 498,408,000 |  |
Commercial real estate | Commercial real estate, owner-occupied |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | 392,345,000 | 304,963,000 |  |
Non-accrual loans | 7,269,000 | 7,147,000 |  |
Non-accrual loans with no allowance | 7,269,000 | 7,147,000 |  |
Commercial real estate | Commercial real estate, owner-occupied | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | 392,345,000 | 304,963,000 |  |
Commercial real estate | Commercial real estate, 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 real estate, 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 real estate, 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 real estate, 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 |  |
Commercial real estate | Commercial real estate, 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 | 392,345,000 | 304,963,000 |  |
Commercial real estate | Commercial real estate, investor-owned |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | 1,189,021,000 | 961,208,000 |  |
Non-accrual loans | 694,000 | 1,610,000 |  |
Non-accrual loans with no allowance | 694,000 | 1,610,000 |  |
Commercial real estate | Commercial real estate, investor-owned | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | 1,189,021,000 | 961,208,000 |  |
Commercial real estate | Commercial real estate, 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 | 1,673,000 |  |
Commercial real estate | Commercial real estate, 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 | 1,673,000 |  |
Commercial real estate | Commercial real estate, 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 real estate, investor-owned | 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 | Commercial real estate, 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 | 1,189,021,000 | 959,535,000 |  |
Commercial real estate | Construction |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | 119,840,000 | 73,046,000 |  |
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 | 119,840,000 | 73,046,000 |  |
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 | 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 | 119,840,000 | 73,046,000 |  |
Residential loans | Home equity |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | 88,746,000 | 104,813,000 |  |
Non-accrual loans | 413,000 | 459,000 |  |
Non-accrual loans with no allowance | 413,000 | 459,000 |  |
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 | 88,746,000 | 104,813,000 |  |
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 | 653,000 | 274,000 |  |
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 | 498,000 | 274,000 |  |
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 | 67,000 | 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 | 88,000 | 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 | 88,093,000 | 104,539,000 |  |
Residential loans | Other residential |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | 114,558,000 | 123,395,000 |  |
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 | 114,558,000 | 123,395,000 |  |
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 | 0 | 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 | 0 | 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 | 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 | 114,558,000 | 123,395,000 |  |
Consumer loans | Installment and other consumer |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | 49,533,000 | 22,723,000 |  |
Non-accrual loans | 0 | 17,000 |  |
Non-accrual loans with no allowance | 0 | 17,000 |  |
Consumer loans | Installment and other consumer | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | 49,533,000 | 22,723,000 |  |
Consumer loans | Installment and other consumer | 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 | 1,036,000 | 758,000 |  |
Consumer loans | Installment and other consumer | 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 | 1,036,000 | 136,000 |  |
Consumer loans | Installment and other consumer | 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 | 622,000 |  |
Consumer loans | Installment and other consumer | 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 |  |
Consumer loans | Installment and other consumer | Current | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | $ 48,497,000 | $ 21,965,000 |  |

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