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Note 4 - 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 | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2014 | Mar. 31, 2013 | Dec. 31, 2013
Summary of Loans Past Due 90 Days or More and Impaired Loans [Abstract] |  |  |  |  |  |
Loans past due 90 days or more and still accruing | $ 163 |  | $ 568 |  | $ 190 |
Ratio of loans past due 90 days or more and still accruing to loans, net of unearned income and deferred fees | 0.03% |  | 0.10% |  | 0.03% |
Accruing restructured loans | 6,145 |  | 5,732 |  | 6,191 |
Impaired loans with no valuation allowance | 10,139 |  | 16,263 |  | 10,372 |
Impaired loans with a valuation allowance | 2,463 |  | 995 |  | 2,613 |
Total impaired loans | 12,602 |  | 17,258 |  | 12,985 |
Valuation allowance | (280) |  | (273) |  | (624) |
Impaired loans, net of allowance | 12,322 |  | 16,985 |  | 12,361 |
Average recorded investment in impaired loans(1) | 13,075 | [1],[2] | 17,935 | [1] | 16,654 | [1],[2]
Interest income recognized on impaired loans, after designation as impaired | $ 99 | [2] | $ 10 |  | $ 267 | [2]
[1] | Recorded investment includes principal net of unearned interest and deferred fees and costs, and accrued interest.
[2] | Only classes with impaired loans are shown.

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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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- Definition Amount of allowance for credit losses related to recorded investment. + 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 (a)(3) -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524 + Details
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- Definition Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without 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 (a)(4) -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524 + Details
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- Definition Amount of unpaid principal balance of impaired financing receivables for which there is no 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 (a)(4) -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524 + Details
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- Definition Unpaid principal balance of impaired financing receivables for which there is 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 (a)(4) -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524 + Details
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