Note 16 - Segment and Geographic Information (Details Textual) $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Number of Reportable Segments	1
Leases [Member]
Sales with Typical Lease Terms (Month)	36 months
System [Member]
Sales with Payment Terms (Month)	12 months
UNITED STATES
Long-Lived Assets	$ 15,203	$ 16,090
Non-US [Member]
Long-Lived Assets	$ 1,916	$ 1,972