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Note 2 - Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Capitalized Computer Software, Net, Ending Balance	$ 49,400
Goodwill, Impairment Loss	0
Advertising Expense	11,600	$ 11,500	$ 13,000
Research and Development Expense, Total	$ 44,241	$ 36,940	$ 32,692
Building [Member]
Property, Plant and Equipment, Useful Life (Year)	39 years
Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Finite-Lived Intangible Asset, Useful Life (Year)	2 years
Minimum [Member] \| Office Space, Manufacturing Facilities, and Certain Company Vehicles and Equipment [Member]
Lessee, Operating Lease, Term of Contract (Year)	1 year
Minimum [Member] \| Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Minimum [Member] \| Office Furniture And Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Minimum [Member] \| Computer Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Minimum [Member] \| Land, Buildings and Improvements [Member]
Property, Plant and Equipment, Useful Life (Year)	10 years
Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	39 years
Finite-Lived Intangible Asset, Useful Life (Year)	12 years
Maximum [Member] \| Office Space, Manufacturing Facilities, and Certain Company Vehicles and Equipment [Member]
Lessee, Operating Lease, Term of Contract (Year)	8 years
Maximum [Member] \| Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)	15 years
Maximum [Member] \| Office Furniture And Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)	7 years
Maximum [Member] \| Computer Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)	5 years
Maximum [Member] \| Land, Buildings and Improvements [Member]
Property, Plant and Equipment, Useful Life (Year)	39 years