Note 6 - Income Taxes (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Operating Loss Carryforwards, Not Subject to Expiration	$ 25,180
Deferred Tax Assets, Valuation Allowance, Total	2,879	$ 1,400
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total	15,135
State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Total	$ 40,032

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws that are not subject to expiration.

No definition available.

+ Details

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

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- Details

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