Note 6 - Investments (Details Textual) $ in Thousands	3 Months Ended
Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($)
Debt Securities, Available-for-Sale, Allowance for Credit Loss	$ 0		$ 0
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	155		191
Limited Liability Investments [Member]
Equity Method Investments	$ 700		$ 700
Equity Method Investment, Other-than-Temporary Impairment	0	$ 0
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	0
Argo Holdings [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	0
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	2,900		2,900
Private Company Investments [Member]
Investment Owned, Fair Value	$ 600		$ 700

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).

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