Note 6 - Investments (Details Textual) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)
Debt Securities, Available-for-Sale, Allowance for Credit Loss	$ 0		$ 0		$ 0
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	209		209		124
Limited Liability Investments [Member]
Equity Method Investment, Other-than-Temporary Impairment	$ 0	$ 0	$ 0	$ 0

Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-9

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (i)
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-URI https://asc.fasb.org/1943274/2147479106/326-30-50-9

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- Definition

Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Subparagraph (b)(3)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Publisher FASB
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- Definition

Amount of other-than-temporary decline in value that has been recognized against investment accounted for under equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481664/323-10-45-1

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