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Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) - Loans Past Due 90 Days or More and Impaired Loans - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2015 | Jun. 30, 2014 | Jun. 30, 2015 | Jun. 30, 2014 | Dec. 31, 2014
Loans Past Due 90 Days or More and Impaired Loans [Abstract] |  |  |  |  |  |  |  |  |  |
Loans past due 90 days or more and still accruing |  | $ 80 | [1] | $ 266 | $ 80 | [1] | $ 266 |  | $ 207 | [1]
Ratio of loans past due 90 days or more and still accruing to loans, net of unearned income and deferred fees |  | 0.01% |  | 0.04% | 0.01% |  | 0.04% |  | 0.03% |
Accruing restructured loans |  | $ 5,943 |  | $ 6,240 | $ 5,943 |  | $ 6,240 |  | $ 6,040 |
Impaired loans: |  |  |  |  |  |  |  |  |  |
Impaired loans with no valuation allowance |  | 12,182 | [2],[3] | 8,155 | 12,182 | [2],[3] | 8,155 |  | 7,615 | [2],[3]
Impaired loans with a valuation allowance |  | 2,503 | [2],[3] | 2,989 | 2,503 | [2],[3] | 2,989 |  | 7,506 | [2],[3]
Total impaired loans |  | 14,685 | [2],[3] | 11,144 | 14,685 | [2],[3] | 11,144 |  | 15,121 | [2],[3]
Valuation allowance |  | (151) | [2] | (291) | (151) | [2] | (291) |  | (282) | [2]
Impaired loans, net of allowance |  | 14,534 |  | 10,853 | 14,534 |  | 10,853 |  | 14,839 |
Average recorded investment in impaired loans(1) | [3] | 15,543 |  | 11,898 | 15,543 | [2] | 11,898 | [2] | 16,311 |
Interest income recognized on impaired loans, after designation as impaired |  | $ 172 |  | $ 191 | $ 172 | [2] | $ 191 | [2] | $ 473 |
[1] | Only classes with past-due or nonaccrual loans are shown.
[2] | Only classes with impaired loans are shown.
[3] | Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.

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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 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=49124121&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=49124121&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=49124121&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=49124121&loc=d3e5212-111524 + Details
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