Note 4 - Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Finite-lived, Gross Carrying Amount	$ 12,080		$ 12,080
Finite-lived, Accumulated Amortization	6,673		6,369
Net Carrying Amount, finite-lived	5,407	$ 5,711	5,711
Intangible Assets, Gross Carrying Amount	18,790		18,790
Net Carrying Amount	12,117	$ 12,421	12,421
Trademarks [Member]
Indefinite-lived, Gross Carrying Amount	6,710		6,710
Net Carrying Amount, indefinite-lived	6,710		6,710
Customer Relationships [Member]
Finite-lived, Gross Carrying Amount	10,480		10,480
Finite-lived, Accumulated Amortization	5,191		4,912
Net Carrying Amount, finite-lived	5,289		5,568
Patented Technology [Member]
Finite-lived, Gross Carrying Amount	600		600
Finite-lived, Accumulated Amortization	498		477
Net Carrying Amount, finite-lived	102		123
Patents [Member]
Finite-lived, Gross Carrying Amount	590		590
Finite-lived, Accumulated Amortization	574		570
Net Carrying Amount, finite-lived	16		20
Computer Software, Intangible Asset [Member]
Finite-lived, Gross Carrying Amount	270		270
Finite-lived, Accumulated Amortization	270		270
Net Carrying Amount, finite-lived
Trade Names [Member]
Finite-lived, Gross Carrying Amount	140		140
Finite-lived, Accumulated Amortization	140		140
Net Carrying Amount, finite-lived

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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