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Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) - Summary of Loans Past Due 90 Days or More and Impaired Loans (USD $) In Thousands, unless otherwise specified | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Summary of Loans Past Due 90 Days or More and Impaired Loans [Abstract] |  |  |  |  |  |
Loans past due 90 days or more and still accruing | $ 190 |  | $ 170 |  |  |
Ratio of loans past due 90 days or more and still accruing to loans, net of unearned income and deferred fees | 0.03% |  | 0.03% |  |  |
Accruing restructured loans | 6,191 |  | 2,005 |  |  |
Impaired loans with no valuation allowance | 10,372 |  | 16,974 |  |  |
Impaired loans with a valuation allowance | 2,613 |  | 1,482 |  |  |
Total impaired loans | 12,985 |  | 18,456 |  |  |
Valuation allowance | (624) |  | (554) |  |  |
Impaired loans, net of allowance | 12,361 |  | 17,902 |  |  |
Average recorded investment in impaired loans(1) | 16,654 | [1] | 13,540 | [1] | 8,734 | [1],[2]
Income recognized on impaired loans, after designation as impaired | 267 |  | 9 |  | 141 | [2]
Amount of income recognized on a cash basis | $ 0 |  | $ 0 |  |  |
[1] | Recorded investment includes principal, accrued interest, and deferred fees and costs.
[2] | Segments reported for December 31, 2011 are presented using the segmentation method in effect for 2011. The Company began reporting under revised segments in 2012.

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- Definition Reflects the carrying amount of loans modified in a troubled debt restructuring that are accruing interest. + References No definition available. + Details
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- Definition Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses, net of allowance. + References No definition available. + Details
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- Definition Represents ratio of loans past due 90 days or more and still accruing to loans, net of unearned income and deferred fees. + References No definition available. + Details
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- Definition Recorded investment in financing receivables that are 90 days or more past due and still accruing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5111-111524 + Details
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- Definition Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5258-111524 + Details
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- Definition Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524 + Details
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