Note 6 - Investments - Loss on Change in Fair Value of Equity Investments (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Net gains recognized on equity investments sold during the period	$ 0	$ 0	$ 0	$ 0
Change in unrealized gains (losses) on equity investments held at end of the period	1,707	(38)	2,782	(48)
Gain (loss) on change in fair value of equity investments	$ 1,707	$ (38)	$ 2,782	$ (48)

Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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- Definition

Amount of unrealized gain (loss) on 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
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
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-Subparagraph (SX 210.7-04(3)(d)(2))
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Amount, after tax and adjustment, of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
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