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Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details Textual) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2016 USD ($) | Mar. 31, 2015 USD ($) | Dec. 31, 2015 USD ($)
Nonperforming Financial Instruments [Member] |  |  |
Interest and Fee Income, Loans and Leases | $ 0 | $ 0 | $ 0
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] | Forgive Principal, Reduce Interest Rate, Capitalize Interest, and Re-amortize Payments [Member] |  |  |
Allowance for Credit Losses, Change in Method of Calculating Impairment |  | 0 |
Financing Receivable Modifications Principal Forgiven |  | $ 100,000 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts |  | 1 |
Commercial Real Estate Portfolio Segment [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts |  | 1 |
Special Mention [Member] |  |  |
Increase in Percentage of Allocation Loans Rated Special Mention | 50.00% |  |
Classified Excluding Impaired [Member] |  |  |
Increase in Percentage of Allocation Loans Rated Classified | 100.00% |  |
Interest and Fee Income, Loans and Leases | $ 7,334,000 | $ 7,610,000 |
Financing Receivable, Reclassification to Held-for-sale | 0 |  |
Transfer of Loans Held-for-sale to Portfolio Loans | $ 0 |  |
Financing Receivable, Modifications, Number of Contracts | 0 |  |
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | 0 | 0 |
Threshold for Designation to Impaired Status | $ 250,000 |  |
Threshold Period for Considering Loans as Special Mention or Classified | 75 days |  |
Financing Receivable, Modifications, Recorded Investment | $ 12,228,000 | $ 12,115,000 | $ 13,453,000

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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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Recorded Investment -URI http://asc.fasb.org/extlink&oid=65880944 + Details
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- Definition The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.1) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
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