Note 7 - Investments - Loss on Change in Fair Value of Equity Investments (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Net gain recognized on equity investments sold during the period	$ 0	$ 13
Change in unrealized losses on equity investments held at end of the period	(26)	(255)
Loss on change in fair value of equity investments	$ (26)	$ (242)

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(3)(d))
-URI https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (f)
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