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Note 2 - Investments (Details Textual) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Equity Securities, FV-NI | $ 17.4 |  | $ 6.2
Equity Securities, FV-NI, Cost | 11.3 |  | $ 9.8
Equity Securities, FV-NI, Unrealized Gain (Loss), Total | 9.4 | $ (1.2) |
Available-for-sale Equity Securities, Acquired During Period, Cost Basis | $ 1.7 | 0.4 |
Available-for-sale Equity Securities, Sold During Period, Cost Basis |  | 0.9 |
Proceeds from Sale of Available-for-sale Securities, Equity |  | 1.8 |
Equity Securities, FV-NI, Realized Gain (Loss), Total |  | $ 0.9 |

X
- Definition This item represents the cost of equity securities acquired during the period, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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- Definition The cost basis of available for sale equity securities sold during the period. + References No definition available. + Details
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- Definition Amount 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/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740 + Details
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- Definition Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value. + References No definition available. + 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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