Note 9 - Fair Values - Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Financial assets
Securities available-for-sale	$ 285,077	$ 286,950
Reported Value Measurement [Member]
Financial assets
Cash and cash equivalents	43,940	80,604
Securities available-for-sale	285,077	286,950
Net loans	1,039,307	1,022,834
Federal Home Loan Bank of San Francisco stock	7,380	7,380
Financial liabilities
Deposits	1,242,387	1,267,171
Term debt	19,969	9,957
Junior subordinated debenture	10,310	10,310
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Financial assets
Cash and cash equivalents	43,940	80,604
Securities available-for-sale
Net loans
Federal Home Loan Bank of San Francisco stock	7,380	7,380
Financial liabilities
Deposits
Term debt
Junior subordinated debenture
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Financial assets
Cash and cash equivalents
Securities available-for-sale	285,077	286,950
Net loans
Federal Home Loan Bank of San Francisco stock
Financial liabilities
Deposits	1,244,030	1,267,153
Term debt	20,272	10,006
Junior subordinated debenture	11,614	13,471
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Financial assets
Cash and cash equivalents
Securities available-for-sale
Net loans	1,051,561	1,025,520
Federal Home Loan Bank of San Francisco stock
Financial liabilities
Deposits
Term debt
Junior subordinated debenture

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(6))
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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- Definition

Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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