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Note 14 - Commitments and Off-balance Sheet Risk (Details) - USD ($) | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2015 | Dec. 31, 2015 | Dec. 31, 2014
Note 14 - Commitments and Off-balance Sheet Risk (Details) [Line Items] |  |  |
Reserve or Liability Balance for Financial Instruments With Off-balance Sheet Risk |  | $ 0 |
Reserve or Liability Balance for Financial Instruments with Off-balance Sheet Risk |  |  | $ 0
Mortgage Loans on Real Estate, Minimum Interest Rate in Range |  | 4.00% |
Mortgage Loans on Real Estate, Maximum Interest Rate in Range |  | 7.00% |
Term Deb tSecured by Real Estate Balloon Payment Period |  | 5 years |
Liabilities for Accreted Fee Collected from Customer |  | $ 100,000 | 100,000
Amount of Federal Reserve Requirement |  | 9,100,000 | $ 8,400,000
Interest Rate Swap [Member] |  |  |
Note 14 - Commitments and Off-balance Sheet Risk (Details) [Line Items] |  |  |
Derivative, Notional Amount |  | 14,700,000 |
Derivative, Fair Value, Net |  | $ (2,300,000) |
Minimum [Member] |  |  |
Note 14 - Commitments and Off-balance Sheet Risk (Details) [Line Items] |  |  |
Amortization Period for Term Debt Secured by Real Estate |  | 10 years |
Interest Rates On Loans Secured by Non-real Estate Collateral |  | 4.00% |
Term Debt Secured by Non-real Estate Collateral, Maturity Period |  | 3 years |
Fees Accreted Into Income During Interest Rate Swap Agreements, Term | 4 years |  |
Maximum [Member] |  |  |
Note 14 - Commitments and Off-balance Sheet Risk (Details) [Line Items] |  |  |
Amortization Period for Term Debt Secured by Real Estate |  | 20 years |
Interest Rates On Loans Secured by Non-real Estate Collateral |  | 7.50% |
Term Debt Secured by Non-real Estate Collateral, Maturity Period |  | 7 years |
Fees Accreted Into Income During Interest Rate Swap Agreements, Term | 15 years |  |

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Amortization period for the payments related to a credit facility, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13495-108611 + Details
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- Definition The highest stated interest rate within the mortgage loans included in the loan grouping. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 10 -Section S99 -Paragraph 6 -Subparagraph (SX 210.5-04.(c) Schedule IV) -URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 310 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-29.3) -URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014 + Details
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