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Note 8 - Commitments and Off-balance Sheet Risk (Details) - Exposure to Credit Losses - USD ($) | Mar. 31, 2016 | Dec. 31, 2015
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Note 8 - Commitments and Off-balance Sheet Risk (Details) - Exposure to Credit Losses [Line Items] |  |
Contractual amounts of financial instruments with off-balance sheet risk | $ 839,429,000 | $ 821,738,000
Loan Origination Commitments [Member] |  |
Note 8 - Commitments and Off-balance Sheet Risk (Details) - Exposure to Credit Losses [Line Items] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 218,392,000 | 178,034,000
Standby Letters of Credit [Member] |  |
Note 8 - Commitments and Off-balance Sheet Risk (Details) - Exposure to Credit Losses [Line Items] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 33,567,000 | 34,946,000
Commercial Portfolio Segment [Member] | Unused lines of Credit [Member] |  |
Note 8 - Commitments and Off-balance Sheet Risk (Details) - Exposure to Credit Losses [Line Items] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 501,735,000 | 522,658,000
1-4 Family Mortgages [Member] | Unused lines of Credit [Member] |  |
Note 8 - Commitments and Off-balance Sheet Risk (Details) - Exposure to Credit Losses [Line Items] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 62,364,000 | 61,905,000
Consumer Portfolio Segment [Member] | Unused lines of Credit [Member] |  |
Note 8 - Commitments and Off-balance Sheet Risk (Details) - Exposure to Credit Losses [Line Items] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 16,874,000 | 15,612,000
Consumer Other Financing Receivable 1 [Member] | Unused lines of Credit [Member] |  |
Note 8 - Commitments and Off-balance Sheet Risk (Details) - Exposure to Credit Losses [Line Items] |  |
Contractual amounts of financial instruments with off-balance sheet risk | $ 6,497,000 | $ 8,583,000

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- Definition The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition. + References Reference 1: 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=73719730&loc=d3e13433-108611 + Details
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