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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
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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Amount excluding accrued interest, before allowance for credit loss, of financing receivable.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of unamortized loan commitment, origination, and other fees (costs) on financing receivable. Excludes financing receivable covered under loss sharing agreement.

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