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Loans and Allowance for Credit Losses on Loans - Outstanding and Aging Analysis (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021 | Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans at amortized cost | $ 2,158,336,000 |  | $ 2,158,336,000 |  | $ 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, accrued interest, writeoff |  |  | 47,000 | $ 0 |
Commercial loans | Commercial and industrial |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans at amortized cost | 207,488,000 |  | 207,488,000 |  | 301,602,000
Commercial real estate loans | Commercial owner-occupied |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans at amortized cost | 368,415,000 |  | 368,415,000 |  | 392,345,000
Commercial real estate loans | Commercial investor-owned |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans at amortized cost | 1,211,651,000 |  | 1,211,651,000 |  | 1,189,021,000
Commercial real estate loans | Construction |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans at amortized cost | 112,154,000 |  | 112,154,000 |  | 119,840,000
Residential loans | Home equity |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans at amortized cost | 89,244,000 |  | 89,244,000 |  | 88,746,000
Residential loans | Other residential |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans at amortized cost | 114,247,000 |  | 114,247,000 |  | 114,558,000
Consumer loans | Installment and other consumer loans |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans at amortized cost | 55,137,000 |  | 55,137,000 |  | 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 | 2,158,336,000 |  | 2,158,336,000 |  | 2,255,645,000
Non-accrual loans | 10,637,000 |  | 10,637,000 |  | 8,376,000
Non-accrual loans with no allowance | 10,637,000 |  | 10,637,000 |  | 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 | 3,670,000 |  | 3,670,000 |  | 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 | 1,527,000 |  | 1,527,000 |  | 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 | 1,834,000 |  | 1,834,000 |  | 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 | 309,000 |  | 309,000 |  | 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 | 2,154,666,000 |  | 2,154,666,000 |  | 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 | 207,488,000 |  | 207,488,000 |  | 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 | 2,736,000 |  | 2,736,000 |  | 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 | 1,007,000 |  | 1,007,000 |  | 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 | 1,474,000 |  | 1,474,000 |  | 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 | 255,000 |  | 255,000 |  | 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 | 204,752,000 |  | 204,752,000 |  | 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 | 368,415,000 |  | 368,415,000 |  | 392,345,000
Non-accrual loans | 9,846,000 |  | 9,846,000 |  | 7,269,000
Non-accrual loans with no allowance | 9,846,000 |  | 9,846,000 |  | 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 | 0 |  | 0 |  | 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 | 0 |  | 0 |  | 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 | 0 |  | 0 |  | 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 | 368,415,000 |  | 368,415,000 |  | 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 | 1,211,651,000 |  | 1,211,651,000 |  | 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 | 1,211,651,000 |  | 1,211,651,000 |  | 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 | 112,154,000 |  | 112,154,000 |  | 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 | 112,154,000 |  | 112,154,000 |  | 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 | 89,244,000 |  | 89,244,000 |  | 88,746,000
Non-accrual loans | 699,000 |  | 699,000 |  | 413,000
Non-accrual loans with no allowance | 699,000 |  | 699,000 |  | 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 | 934,000 |  | 934,000 |  | 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 | 520,000 |  | 520,000 |  | 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 | 360,000 |  | 360,000 |  | 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 | 88,310,000 |  | 88,310,000 |  | 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 | 114,247,000 |  | 114,247,000 |  | 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 | 114,247,000 |  | 114,247,000 |  | 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 | 55,137,000 |  | 55,137,000 |  | 49,533,000
Non-accrual loans | 92,000 |  | 92,000 |  | 0
Non-accrual loans with no allowance | 92,000 |  | 92,000 |  | 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 | 0 |  | 0 |  | 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 | 0 |  | 0 |  | 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 | 0 |  | 0 |  | 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 | $ 55,137,000 |  | $ 55,137,000 |  | $ 48,497,000

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