Note 10 - Leases (Details Textual)	Dec. 31, 2020 ft²	Jan. 30, 2020
Additional Number of Leases	4
Operating Lease, Weighted Average Remaining Lease Term (Year)	3 years 14 days
Operating Lease, Weighted Average Discount Rate, Percent	4.68%
UNITED STATES
Debt Instrument, Interest Rate, Effective Percentage	5.25%
ITALY
Debt Instrument, Interest Rate, Effective Percentage	2.67%
Minimum [Member]
Lessee, Operating Lease, Term of Contract (Year)	1 year
Maximum [Member]
Lessee, Operating Lease, Term of Contract (Year)	4 years
Office Building [Member] \| Gallarate Italy [Member]
Area of Real Estate Property (Square Foot)	1,335
Office Building [Member] \| Aurora Illinois [Member]]
Area of Real Estate Property (Square Foot)	11,000
Lessee, Operating Lease, Term of Contract (Year)		3 years
Office Building [Member] \| Overland Park [Member]
Area of Real Estate Property (Square Foot)	600

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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