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Loans and Allowance for Credit Losses on Loans - Schedule of Loans by Class (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Jun. 30, 2023 | Dec. 31, 2022 | Sep. 30, 2022 | Jun. 30, 2022 | Dec. 31, 2021
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Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans, at amortized cost | $ 2,086,942 |  | $ 2,092,546 |  |  |
Allowance for credit losses on loans | (24,260) | $ (23,832) | (22,983) | $ (22,963) | $ (22,539) | $ (23,023)
Total loans, net of allowance for credit losses on loans | 2,062,682 |  | 2,069,563 |  |  |
Net deferred loan origination costs | 2,600 |  | 1,800 |  |  |
Unrecognized purchase discounts on non-PCI loans | 2,200 |  | 2,600 |  |  |
Financing receivable, accrued interest, net | 6,300 |  | 6,100 |  |  |
Commercial loans | Commercial and industrial |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans, at amortized cost | 174,096 |  | 173,547 |  |  |
Allowance for credit losses on loans | (1,808) | (1,831) | (1,794) | (1,958) | (1,699) | (1,709)
Commercial real estate loans | Commercial owner-occupied |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans, at amortized cost | 346,307 |  | 354,877 |  |  |
Allowance for credit losses on loans | (2,530) | (2,589) | (2,487) | (2,536) | (2,617) | (2,776)
Commercial real estate loans | Commercial non-owner occupied |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans, at amortized cost | 1,190,813 |  | 1,191,889 |  |  |
Allowance for credit losses on loans | (13,624) | (13,201) | (12,676) | (12,738) | (12,439) |
Commercial real estate loans | Construction |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans, at amortized cost | 109,305 |  | 114,373 |  |  |
Allowance for credit losses on loans | (2,018) | (1,942) | (1,937) | (1,784) | (1,737) | (1,653)
Residential loans | Home equity |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans, at amortized cost | 83,267 |  | 88,748 |  |  |
Allowance for credit losses on loans | (565) | (561) | (558) | (542) | (530) | (595)
Residential loans | Other residential |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans, at amortized cost | 116,674 |  | 112,123 |  |  |
Allowance for credit losses on loans | (605) | (599) | (595) | (590) | (585) | (644)
Consumer loans | Installment and other consumer loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans, at amortized cost | 66,480 |  | 56,989 |  |  |
Allowance for credit losses on loans | $ (951) | $ (940) | $ (868) | $ (815) | $ (733) | $ (621)

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