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Loans and Allowance for Credit Losses on Loans - CARES Act Narrative (Details) $ in Thousands | Mar. 31, 2022 USD ($) branch loan | Dec. 31, 2021 USD ($) loan | Aug. 06, 2021 USD ($) branch | Jun. 30, 2021 USD ($) loan
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Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans at amortized cost | $ 2,201,854 | $ 2,255,645 |  |
SBA PPP |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Number of PPP participated | branch | 2 |  |  |
Commercial loans | Commercial and industrial |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans at amortized cost | $ 248,625 | $ 301,602 |  |
Commercial loans | Commercial and industrial | SBA PPP |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Number of loans | loan | 191 | 368 |  | 2,876
Loans at amortized cost | $ 40,600 | $ 111,200 |  | $ 444,100
Financing receivable, unamortized loan fee | $ 993 | $ 2,500 |  |
Commercial loans | Commercial and industrial | SBA PPP | American River Bank (ARB) |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Number of loans | branch |  |  | 113 |
Loans at amortized cost |  |  | $ 18,600 |

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