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Borrowings and Other Obligations - Schedule of Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Aug. 06, 2021
Debt Instrument [Line Items]
FHLB fixed-rate advances, Carrying Value	$ 0	$ 0	$ 0
FHLB fixed-rate advances, Average Balance	$ 0	$ 642	$ 0
FHLB fixed-rate advances, Average Rate	0.00%	1.18%	0.00%
Other obligations (finance leases)
Debt Instrument [Line Items]
Other Obligations Carrying Value	$ 439	$ 419	$ 58
Other Obligations Average Balance	$ 374	$ 250	$ 132
Borrowings, Average Rate	0.65%	0.71%	2.62%
Subordinated debenture
Debt Instrument [Line Items]
Subordinated debenture, Carrying Value	$ 0	$ 0	$ 2,777
Subordinated debenture, Average Balance	$ 0	$ 534	$ 2,741
Borrowings, Average Rate	0.00%	251.54%	5.68%
Line of Credit | American River Bank ARB | Federal Home Loan Bank Borrowings
Debt Instrument [Line Items]
Lines of credit				$ 13,900
Federal Home Loan Bank Borrowings | Line of Credit
Debt Instrument [Line Items]
FHLB overnight borrowings and advances, Carrying Value	$ 112,000	$ 0	$ 0
FHLB overnight borrowings and advances, Average Balance	$ 1,921	$ 0	$ 42
Borrowings, Average Rate	4.48%	0.00%	0.75%
Federal Home Loan Bank Borrowings | Line of Credit | Federal Home Loan Bank Borrowings
Debt Instrument [Line Items]
Borrowings, Average Rate	4.65%

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Federal Home Loan Bank, Advances, Average Balance, Fixed Rate

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Other Obligations Carrying Value

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Weighted average interest rate of debt outstanding.

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Par amount of advances made and reported by Federal Home Loan Bank (FHLBank) with fixed interest rate.

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Weighted average interest rate on advances made and reported by Federal Home Loan Bank (FHLBank).

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Average amount borrowed under the credit facility during the period.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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