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Note 10 - Derivative Financial Instruments (Details Textual) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
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Foreign Exchange Forward [Member] |  |
Derivative, Notional Amount | $ 0 | $ 0
Eurodollar Future [Member] |  |
Derivative, Notional Amount | 0 | 0
TBA and Other Forward MBS [Member] | Long [Member] |  |
Derivative, Notional Amount | 1,706,834 | 1,773,000
TBA and Other Forward MBS [Member] | Short [Member] |  |
Derivative, Notional Amount | 1,809,550 | 1,874,194
Other Extended Settlement Trade [Member] | Long [Member] |  |
Derivative, Notional Amount |  | $ 1,526
Other Extended Settlement Trade [Member] | Short [Member] |  |
Derivative, Notional Amount | $ 365 |

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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959 + Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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