Note 4 - Loans and Allowance for Credit Losses (Details) - Troubled debt restructurings (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2013	Dec. 31, 2012
Financing Receivable, Modifications [Line Items]
Number of Contracts	7	5
Pre-Modification Carrying Value	$ 8,286	$ 6,709
Period-End Carrying Value	8,014	6,678
Period-End Individual Impairment Allowance	147	797
Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	4	3
Pre-Modification Carrying Value	1,991	1,318
Period-End Carrying Value	1,759	1,196
Period-End Individual Impairment Allowance		797
Commercial Real Estate Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	3	2
Pre-Modification Carrying Value	6,295	5,391
Period-End Carrying Value	6,255	5,482
Period-End Individual Impairment Allowance	$ 147

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953676-111524

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

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- Definition

The amount of the impairment allowance related to financing receivables that have been modified by troubled debt restructurings.

+ References

No definition available.

+ Details

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