Note 7 - Related Party Transactions - Transactions With Related Parties (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Income	$ 1,108	$ 1,179	$ 2,950	$ 3,135
Expense	(988)	(1,041)	(2,820)	(2,681)
Assets	43,284		43,284		$ 43,145
Liabilities	1,378		1,378		$ 1,905
GAMCO Investors, Inc. [Member]
Income	177	444	891	1,293
Expense	0	0	0	0
Assets		35,515		35,515		$ 34,242
Liabilities		0		0		0
Mtron Industries Inc [Member]
Income	0	0	0	0
Expense	40	(15)	48	(44)
Assets		0		0		0
Liabilities		196		196		59
Related Party [Member]
Income	177	444	891	1,293
Expense	$ 40	(15)	$ 48	(44)
Assets		35,515		35,515		34,242
Liabilities		$ 196		$ 196		$ 59