Note 1 - Basis of Presentation - Revenues and Profit (Loss) Allocations to Reportable Segments (Details) - USD ($)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Revenues	$ 4,925,000	$ 4,847,000
Net Income (Loss) Attributable to Parent	188,000	269,000
Domestic Segment [Member]
Revenues	4,229,000	4,141,000
Net Income (Loss) Attributable to Parent	255,000	276,000
Foreign Segment [Member]
Revenues	696,000	706,000
Net Income (Loss) Attributable to Parent	$ (67,000)	$ (7,000)