Note 9 - Significant Risk Concentrations (Details Textual) - USD ($)	6 Months Ended
Jun. 30, 2022	Dec. 31, 2021
Accounts Receivable, after Allowance for Credit Loss, Current, Total	$ 5,616,000	$ 4,914,000
GES Manufacturing [Member]
Accounts Receivable, after Allowance for Credit Loss, Current, Total	$ 900,000
GES Manufacturing [Member] \| Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Concentration Risk, Percentage	17.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
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-URI https://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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