Note 4 - Intangible Assets - Intangible Assets (Details) - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2022
Finite-lived intangible assets, gross	$ 7,352,346	$ 7,352,346
Less: Accumulated amortization	2,280,315	2,364,221
Net	5,072,031	4,988,125
Lighting Patent [Member]
Finite-lived intangible assets, gross	$ 6,797,000	6,797,000
Finite-Lived Intangible Asset, Useful Life (Year)	16 years
Technology-Based Intangible Assets [Member]
Finite-lived intangible assets, gross	$ 276,080	276,080
Customer Relationships [Member]
Finite-lived intangible assets, gross	$ 149,872	149,872
Finite-Lived Intangible Asset, Useful Life (Year)	7 years
Computer Software, Intangible Asset [Member]
Finite-lived intangible assets, gross	$ 105,730	105,730
Trade Names [Member]
Finite-lived intangible assets, gross	$ 23,664	$ 23,664
Finite-Lived Intangible Asset, Useful Life (Year)	3 years

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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- Definition

Accumulated amount of 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 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(16))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

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 https://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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

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- Definition

Amount after 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 926
-SubTopic 20
-Section 50
-Paragraph 5
-URI https://asc.fasb.org/extlink&oid=120154696&loc=d3e54445-107959

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-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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