Note 10 - Income Tax Benefit (Details Textual) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2018
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total	$ 25.0	$ 10.8
Reduction of Operating Loss Carryforward, Tax Audit	$ 1.3
Open Tax Year	2017 2018 2019 2020
State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Total	$ 30.0
Open Tax Year	2017 2018 2019 2020

The amount of reduction in operating loss carryforward due to completion of tax audit.

No definition available.

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- Definition

Tax year that remains open to examination under enacted tax laws, in CCYY format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

+ Details

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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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