Note 5 - Loans and Allowance for Loan Losses (Detail) - Additional Information Regarding Troubled Debt Restructurings (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Number of loans	18	18
Commercial Real Estate Investor Income Producing [Member] \| Modified in Current Year [Member]
Number of loans	1
Pre-modification outstanding recorded investment	3,610
Post-modification outstanding recorded investment	3,610
Residential Mortgage Loans [Member] \| Modified in Current Year [Member]
Number of loans	1
Pre-modification outstanding recorded investment	43
Post-modification outstanding recorded investment	43
Modified in Current Year [Member]
Number of loans	2
Pre-modification outstanding recorded investment	3,653
Post-modification outstanding recorded investment	3,653

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

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=7512638&loc=SL6953676-111524

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- Definition

Amount of investment in financing receivables (after modification) modified by troubled debt restructurings.

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- Definition

Amount of investment in financing receivables (before modification) modified by troubled debt restructurings.

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