Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Foreign Currency Transaction Gain (Loss), before Tax, Total	$ (1,364)	$ (310)	$ 953
Goodwill, Impairment Loss	$ 0	0	0
Minimum [Member]
Warranty Term (Year)	1 year
Maximum [Member]
Warranty Term (Year)	2 years
Building and Building Improvements [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	20 years
Building and Building Improvements [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	40 years
Computer Equipment [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Computer Equipment [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	8 years
Transportation Equipment [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	5 years
Transportation Equipment [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	20 years
Furniture and Fixtures [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Furniture and Fixtures [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	5 years
Interest and Other Income [Member]
Foreign Currency Transaction Gain (Loss), before Tax, Total	$ (1,400)	$ (300)	$ 1,000