Note 10 - Federal Funds Purchased and Lines of Credit (Details Textual)	Jun. 30, 2016 USD ($)	Dec. 31, 2015 USD ($)
Federal Home Loan Bank FHLB [Member]
Long-term Line of Credit	$ 0	$ 75,000,000
Federal Home Loan Bank of San Francisco Affordable Housing Grant Sponsorships [Member]
Line of Credit Facility, Maximum Borrowing Capacity	295,100,000
Federal Reserve [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 34,500,000
Minimum [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate	0.60%
Maximum [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate	1.36%
Federal Funds Purchased	$ 0	$ 0
Line of Credit Facility Number of Lenders	3
Collateralized Agreements	$ 40,000,000

The number of lenders granting funds under lines of credit.

No definition available.

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- Definition

The total of collateralized agreements including securities purchased under agreements to resell (repos), borrowed securities, and secured demand notes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(2)(i)(A))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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-Section 05
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-URI http://asc.fasb.org/extlink&oid=64836671&loc=d3e93640-111703

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- Definition

Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(1))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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