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Loans and Allowance for Credit Losses - CARES Act Narrative (Details) $ in Thousands | Dec. 31, 2022 USD ($) loan | Dec. 31, 2021 USD ($) loan | Aug. 06, 2021 USD ($) loan | Dec. 31, 2020 USD ($) round loan
--- | --- | --- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | $ 2,092,546 | $ 2,255,645 |  |
Small Business Administration Paycheck Protection Program |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Number of PPP rounds participated | round |  |  |  | 2
Commercial | Commercial and industrial |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans, at amortized cost | $ 173,547 | $ 301,602 |  |
Commercial | Commercial and industrial | Small Business Administration Paycheck Protection Program |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Number of loans | loan | 18 | 368 |  | 2,876
Loans, at amortized cost | $ 3,500 | $ 111,200 |  | $ 444,100
Unrecognized loan fees, net of costs | $ 99 | $ 2,500 |  |
Commercial | Commercial and industrial | Small Business Administration Paycheck Protection Program | American River Bank ARB |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Number of loans | loan |  |  | 113 |
Loans, at amortized cost |  |  | $ 18,600 |

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