Note 6 - Goodwill and Other Intangible Assets - Summary of Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Amortizing intangible assets	$ 12,250	$ 12,270
Accumulated amortization	(11,806)	(11,733)
Other intangible assets, net	1,635	1,728
Customer Relationships [Member]
Amortizing intangible assets	9,318	9,338
Technology-Based Intangible Assets [Member]
Amortizing intangible assets	1,360	1,360
Trade Names [Member]
Amortizing intangible assets	1,572	1,572
Trade Names 1 [Member]
Indefinite trade name	$ 1,191	$ 1,191

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

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-Publisher FASB
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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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-Publisher FASB
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