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Loans and Allowance for Credit Losses on Loans - CARES Act Narrative (Details) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2021 USD ($) loan branch | Dec. 31, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Loans at amortized cost | $ 2,317,019 | $ 2,088,556
SBA PPP |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Number of loans | loan | 871 |
SBA PPP | American River Bank (ARB) |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Number of loans funded during period | branch | 31 |
Loans at amortized cost | $ 9,600 |
SBA PPP Round Two |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Number of loans funded during period | loan | 790 |
Commercial loans | Commercial and industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Loans at amortized cost | $ 377,965 | 498,408
Commercial loans | Commercial and industrial | SBA PPP |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Loans at amortized cost | 164,800 | 291,600
Financing receivable, unamortized loan fee | 4,200 | $ 5,400
Commercial loans | Commercial and industrial | SBA PPP Round Two |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Loans at amortized cost | $ 123,900 |

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