Note 10 - Income Taxes - Net Operating Losses and Tax Credit Carryforwards (Details) - Domestic Tax Authority [Member] $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($)
Net operating losses--federal	$ 12,958
Tax credits--federal	$ 235
Earliest Tax Year [Member]
Net operating losses--federal	2031
Tax credits--federal	2041
Tax Year 2018 [Member]
Net operating losses--federal	$ 12,068

Expiration date of each operating loss carryforward included in operating loss carryforward, in CCYY format.

No definition available.

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- Definition

Expiration year of the tax credit carryforward, in CCYY format.

+ References

No definition available.

+ Details

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Data Type:	xbrli:gYearItemType
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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=121826272&loc=d3e32559-109319

+ Details

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

+ Details

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- Details

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- Details

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- Details

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