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Note 8 - Commitments and Off-Balance Sheet Risk - Exposure to Credit Losses (Details) - USD ($) | Jun. 30, 2019 | Dec. 31, 2018
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Contractual amounts of financial instruments with off-balance sheet risk | $ 1,019,325,000 | $ 1,036,775,000
Standby Letters of Credit [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 22,515,000 | 25,322,000
Unused lines of Credit [Member] | Commercial Portfolio Segment [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 773,984,000 | 784,895,000
Unused lines of Credit [Member] | One to Four Family Mortgages [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 58,910,000 | 57,378,000
Unused lines of Credit [Member] | Consumer Portfolio Segment [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 53,475,000 | 47,432,000
Unused lines of Credit [Member] | Consumer Other Financing Receivable 1 [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 19,178,000 | 20,231,000
Loan Origination Commitments [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | $ 91,263,000 | $ 101,517,000

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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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611 + Details
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