Note 9 - Fair Values - Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale	$ 337,032	$ 286,950
Financial liabilities
Debt Securities, Available-for-sale	337,032	286,950
Reported Value Measurement [Member]
Cash and cash equivalents	127,883	80,604
Debt Securities, Available-for-sale	337,032	286,950
Net loans	1,188,155	1,022,834
Federal Home Loan Bank of San Francisco stock	7,380	7,380
Financial liabilities
Deposits	1,518,131	1,267,171
Term debts	19,993	9,957
Junior subordinated debenture	10,310	10,310
Cash and cash equivalents	127,883	80,604
Debt Securities, Available-for-sale	337,032	286,950
Net loans	1,188,155	1,022,834
Federal Home Loan Bank of San Francisco stock	7,380	7,380
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	127,883	80,604
Debt Securities, Available-for-sale	0	0
Net loans	0	0
Federal Home Loan Bank of San Francisco stock	7,380	7,380
Financial liabilities
Deposits	0	0
Term debts	0	0
Junior subordinated debenture	0	0
Cash and cash equivalents	127,883	80,604
Debt Securities, Available-for-sale	0	0
Net loans	0	0
Federal Home Loan Bank of San Francisco stock	7,380	7,380
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0	0
Debt Securities, Available-for-sale	337,032	286,950
Net loans	0	0
Federal Home Loan Bank of San Francisco stock	0	0
Financial liabilities
Deposits	1,519,635	1,267,153
Term debts	20,232	10,006
Junior subordinated debenture	9,783	13,471
Cash and cash equivalents	0	0
Debt Securities, Available-for-sale	337,032	286,950
Net loans	0	0
Federal Home Loan Bank of San Francisco stock	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0	0
Debt Securities, Available-for-sale	0	0
Net loans	1,205,297	1,025,520
Federal Home Loan Bank of San Francisco stock	0	0
Financial liabilities
Deposits	0	0
Term debts	0	0
Junior subordinated debenture	0	0
Cash and cash equivalents	0	0
Debt Securities, Available-for-sale	0	0
Net loans	1,205,297	1,025,520
Federal Home Loan Bank of San Francisco stock	$ 0	$ 0

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
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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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.

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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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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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