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Note 8 - Commitments and Off-balance Sheet Risk - Exposure to Credit Losses (Details) - USD ($) | Jun. 30, 2016 | Dec. 31, 2015
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Unused lines of Credit [Member] | Commercial Portfolio Segment [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | $ 516,345,000 | $ 522,658,000
Unused lines of Credit [Member] | One to Four Family Mortgages [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 59,163,000 | 61,905,000
Unused lines of Credit [Member] | Consumer Portfolio Segment [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 18,295,000 | 15,612,000
Unused lines of Credit [Member] | Consumer Other Financing Receivable 1 [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 6,970,000 | 8,583,000
Loan Origination Commitments [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 212,873,000 | 178,034,000
Standby Letters of Credit [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 33,206,000 | 34,946,000
Contractual amounts of financial instruments with off-balance sheet risk | $ 846,852,000 | $ 821,738,000

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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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