Note 7 - Related Party Transactions (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Mar. 31, 2025	Dec. 31, 2024	Oct. 07, 2022
Income Taxes Paid			$ 47	$ 76
GAMCO Investors, Inc. [Member]
Investment Expense Rate	0.08%	0.08%	0.08%	0.08%
Funds Invested in Mutual Funds	$ 35,515		$ 35,515			$ 34,242
Income From Mutual Funds	177	$ 471	891	$ 1,293
MtronPTI [Member]
Percentage of Shares Distribution Under Spinoff							100.00%
Salaries and Benefits Reimbursed	28	27	12	80
MtronPTI [Member] | Transitional Administrative and Management Services Agreement [Member]
Monthly Payment					$ 4
Related Party Transaction, Amounts of Transaction	12	12	36	36
MtronPTI [Member] | Tax Indemnity and Sharing Agreement [Member]
Income Taxes Paid	$ 0	$ 0	$ 0	$ 0