Note 4 - Investments (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Proceeds from Sale and Maturity of Marketable Securities	$ 0	$ 16,947
Marketable Security, Realized Gain (Loss)	$ (0)	$ (4,316)
Iron Net [Member] | Discontinued Operations, Disposed of by Sale [Member]
Investment Owned, Balance, Shares (in shares)		198,250
GAMCO Investors, Inc. [Member] | Discontinued Operations, Disposed of by Sale [Member]
Proceeds from Sale and Maturity of Marketable Securities		$ 16,886
Marketable Security, Realized Gain (Loss)		$ 370