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Note 9 - Investments in Marketable Securities (Details Textual) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Equity Securities Fv Ni Gross Unrealized Gain | $ 98,459,000 |  | $ 84,514,000
Equity Securities Fv Ni Gross Unrealized Loss | 474,000 |  | 928,000
Equity Securities, FV-NI, Unrealized Gain (Loss) | 14,399,000 | $ 1,386,000 |
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax | 179,000 |  | 326,000
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax | 8,273,000 |  | $ 7,937,000
Proceeds from Sale and Maturity of Marketable Securities | 11,615,000 | 15,492,000 |
Debt Securities, Realized Gain (Loss) | $ 344,000 | $ (492,000) |

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- Definition The amount of gross unrealized gains from equity securities measured at fair value with gains losses reported on the income statement. + References No definition available. + Details
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- Definition The gross unrealized loss on equity securities measured at fair value with gains and losses recognized on the income statement. + References No definition available. + Details
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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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- Definition Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(9)(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(7)(c)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(3)(d)(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 + Details
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