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Note 7 - Investment and Equity Securities (Details Textual) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Equity Securities, FV-NI, Unrealized Gain (Loss), Total | [1] | $ (160,000) | $ 58,000 |
Equity Securities, FV-NI, Realized Gain (Loss), Total |  | 0 | 0 |
Proceeds from Sale of Debt Securities, Available-for-sale |  | 0 | 0 |
Security Owned and Pledged as Collateral, Fair Value, Total |  | $ 53,100,000 |  | $ 55,600,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Total |  | 86 |  |
Available-for-sale Securities, Percentage of Portfolio |  | 96.00% |  |
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held, Ending Balance |  | $ 0 | $ 0 |
[1] | Not within scope of ASC 606

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- Definition Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27290-111563 + Details
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- Definition Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117546-209714 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(3)(d)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 + Details
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