Note 12 - Fair Values - Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Securities held-to-maturity	$ 32,549
Securities available-for-sale, at fair value	209,609	$ 175,174
Reported Value Measurement [Member]
Securities held-to-maturity	31,329	31,187
Net loans	805,241	793,991
Federal Home Loan Bank of San Francisco stock	4,537	4,465
Deposits	1,046,225	1,004,666
Term debt	18,139	18,733
Junior subordinated debenture	10,310	10,310
Cash and cash equivalents	96,854	68,407
Securities available-for-sale, at fair value	209,609	175,174
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities held-to-maturity
Net loans
Federal Home Loan Bank of San Francisco stock	4,537	4,465
Deposits
Term debt
Junior subordinated debenture
Cash and cash equivalents	96,854	68,407
Securities available-for-sale, at fair value
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities held-to-maturity	32,549	31,374
Net loans
Federal Home Loan Bank of San Francisco stock
Deposits	1,046,028	1,004,729
Term debt	18,537	18,726
Junior subordinated debenture	9,414	9,077
Cash and cash equivalents
Securities available-for-sale, at fair value	209,609	175,174
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities held-to-maturity
Net loans	815,194	797,114
Federal Home Loan Bank of San Francisco stock
Deposits
Term debt
Junior subordinated debenture
Cash and cash equivalents
Securities available-for-sale, at fair value

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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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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-Publisher FASB
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Fair value of investments in debt securities classified as held-to-maturity.

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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.

+ References

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