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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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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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-Publisher FASB
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Amount of unamortized loan commitment, origination, and other costs (fees) on financing receivable recognized as adjustment to yield. Excludes financing receivable covered under loss sharing agreement.

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