Note 1 - Summary of Significant Accounting Policies - Schedule of Finite-lived Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Gross carrying amount	$ 2,338	$ 2,293
Accumulated amortization	1,166	1,120
Net book value	$ 1,172	$ 1,173	[1]
Customer Relationships [Member]
Remaining lives (Year)	9 years	9 years
Gross carrying amount	$ 1,302	$ 1,302
Accumulated amortization	832	795
Net book value	$ 470	$ 507
Intellectual Property [Member]
Remaining lives (Year)	3 years	3 years
Gross carrying amount	$ 100	$ 100
Accumulated amortization	100	100
Net book value
Trade Names [Member]
Remaining lives (Year)	20 years	20 years
Gross carrying amount	$ 814	$ 814
Accumulated amortization	234	225
Net book value	$ 580	$ 589
Patents [Member]
Remaining lives (Year)	7 years	7 years
Gross carrying amount	$ 122	$ 77
Accumulated amortization
Net book value	$ 122	$ 77

[1] The balance sheet at December 31, 2020 has been derived from the audited financial statements at that date