Note 7 - Selected Balance Sheet Data - Finite-lived Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Carrying amount, gross	$ 13,125	$ 13,125
Accumulated amortization	(3,334)	(2,340)
Carrying amount, net	9,791	10,785
Customer Lists [Member]
Carrying amount, gross	6,400	6,400
Accumulated amortization	(867)	(467)
Carrying amount, net	5,533	5,933
Technology-Based Intangible Assets [Member]
Carrying amount, gross	6,725	6,725
Accumulated amortization	(2,467)	(1,873)
Carrying amount, net	$ 4,258	$ 4,852

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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