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Note 4 - Investment Securities (Details Textual) | 12 Months Ended
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Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Proceeds from Sale of Mortgage Backed Securities (MBS) categorized as Available-for-sale | $ 0 | $ 605,200,000
Proceeds from Maturities, Prepayments and Calls of Mortgage Backed Securities (MBS) | 71,600,000 | 153,000,000
Proceeds From Sales And Repayments Of Other Investment Securities | 111,700,000 | 294,000
Proceeds from Maturities Repayments and Calls of Other Investment Securities | 491,000,000 | 460,000,000
Realized Gain From Sale And Call Of Investment Securities | 1,700,000 | 5,100,000
Realized Loss From Sale And Call Of Investment Securities | $ 710,000 | $ 0
Temporarily Impaired Securities As Percentage Of Investment Securities | 88.60% |
Percentage Of Unrealized Losses For Securities With Unrealized Losses For Less Than Twelve Months | 0.60% |
Percentage Of Unrealized Losses For Securities With Unrealized Losses For Greater Than Twelve Months | 2.10% |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 24 | 7
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year | 63 | 30
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | $ 16,684,000 | $ 14,968,000
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities | 0 |
Pledged Investment Securities | $ 272,200,000 | $ 649,100,000

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- Definition Percentage of Unrealized Losses for Securities with Unrealized Losses for Greater than Twelve Months + References No definition available. + Details
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- Definition Percentage of Unrealized Losses for Securities with Unrealized Losses for Less Than Twelve Months + References No definition available. + Details
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- Definition Pledged investment securities at carrying value. + References No definition available. + Details
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- Definition Proceeds from maturities repayments and calls of other investment securities. + References No definition available. + Details
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- Definition Proceeds From Sales and Repayments of Other Investment Securities + References No definition available. + Details
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- Definition Realized gain from sale and call of investment securities + References No definition available. + Details
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- Definition Temporarily impaired securities as percentage of investment securities. + References No definition available. + Details
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- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
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- Definition Number of investment positions in available-for-sale investments in a continuous unrealized loss position for less than one year or normal operating cycle, if longer, for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References No definition available. + Details
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- Definition Number of investment positions in available-for-sale investments that have been in a continuous unrealized loss position for greater than or equal to a year for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References No definition available. + Details
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- Definition The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 8A -URI http://asc.fasb.org/extlink&oid=82896770&loc=SL6284422-111562 + Details
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- Definition The cash inflow from the maturity (principal due), prepayment and call (request of early payment) of a loan financed by home mortgage payments classified as held to maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585 + Details
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- Definition The cash inflow from the sale of securities issued by a governmental agency or corporation (for example, GNMA or FHLMC) or by private issuers (for example, banks and mortgage banking enterprises) secured by and repaid from underlying mortgages, which were designated as available for sale when acquired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585 + Details
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