Note 7 - Assets Held for Rent - Assets Held for Rent (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Shippers placed in service	$ 8,132	$ 7,671
Fixed assets held for rent	4,686	4,686
Accumulated depreciation	(5,451)	(4,952)
Subtotal	7,367	7,405
Shippers and related components in production	1,638	1,659
Total	$ 9,005	$ 9,064