Note 8 - Borrowings (Details Textual) - USD ($)		12 Months Ended
Mar. 25, 2021	Dec. 31, 2021	Dec. 31, 2020
Federal Home Loan Bank, Advances, Maximum Available Credit to Bank Assets, Percentage		40.00%
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged		$ 699,500,000	$ 641,700,000
Subordinated Debt, Ending Balance		39,280,000	0
Proceeds from Issuance of Subordinated Long-term Debt		39,223,000	0
Debt Instrument, Notes Due 2031 [Member]
Subordinated Debt, Ending Balance	$ 40,000,000.0
Debt Instrument, Interest Rate, Stated Percentage	3.75%
Proceeds from Issuance of Subordinated Long-term Debt	$ 39,300,000
Proceeds from Equity Method Investment, Distribution, Return of Capital	$ 20,000,000.0
Federal Home Loan Bank of San Francisco [Member]
Federal Reserve Bank Advances		0
Securities Investment [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged		0	$ 152,000
Securities Investment [Member] \| Federal Home Loan Bank of San Francisco [Member]
Federal Reserve Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged		$ 17,200,000

The percentage of maximum available credit to bank assets for advances from federal home loan bank.

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- Definition

Amount of advances from Federal Reserve Bank.

+ References

No definition available.

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- Definition

Amount of the collateral pledged in support of federal reserve bank advances outstanding.

+ References

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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- Definition

Amount of distribution received from equity method investee for return of investment, classified as investing activities. Excludes distribution for return on investment, classified as operating activities.

+ References

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- Definition

The cash inflow from a borrowing where a lender is placed in a lien position behind debt having a higher priority of repayment (senior) in liquidation of the entity's assets or underlying collateral.

+ References

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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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