Note 3 - Segment Information - Assets and Capital Expenditures (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Total assets	$ 43,302	$ 43,145
Corporate Segment [Member]
Total assets	17,311	17,148
Operating Segments [Member]
Total assets	43,302	43,145
Operating Segments [Member] | Electronic Instruments [Member]
Total assets	998	1,249
Operating Segments [Member] | Merchant Investment [Member]
Total assets	24,993	24,748
Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment [Member]
Total assets	$ 0	$ 0