Note 6 - Intangible Assets - Intangible Assets (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Finite-lived intangible assets, gross	$ 7,462,437	$ 6,797,000
Less: Accumulated amortization	2,183,570	1,840,853
Net	5,278,867	4,956,147
Lighting Patent [Member]
Finite-lived intangible assets, gross	6,797,000	6,797,000
Technology-Based Intangible Assets [Member]
Finite-lived intangible assets, gross	345,356	0
Customer Relationships [Member]
Finite-lived intangible assets, gross	219,772	0
Computer Software, Intangible Asset [Member]
Finite-lived intangible assets, gross	53,215	0
Trade Names [Member]
Finite-lived intangible assets, gross	$ 47,094	$ 0

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
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-Name Accounting Standards Codification
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