Note 7 - Intangible Assets - Schedule of Intangible Assets (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Accumulated amortization	$ (25,326,058)	$ (24,160,885)
Balance	40,252,646
Total, cost	70,085,793	68,534,794
Intangible assets, net	44,759,735	44,373,909
Easements [Member]
Accumulated amortization	0	0
Balance	4,507,089	4,507,089
Customer Relationships [Member]
Cost	48,087,482	46,740,483
Accumulated amortization	(21,353,075)	(20,558,751)
Balance	26,734,407	26,181,732
Permits, Licenses and Lease Acquisition Costs [Member]
Cost	11,257,673	11,053,673
Accumulated amortization	(2,665,384)	(2,412,313)
Balance	8,592,289	8,641,360
Site Location [Member]
Cost	849,347	849,347
Accumulated amortization	(207,426)	(193,462)
Balance	641,921	655,885
Noncompete Agreements [Member]
Cost	626,000	626,000
Accumulated amortization	(414,405)	(386,934)
Balance	211,595	239,066
Trademarks and Trade Names [Member]
Cost	3,602,202	3,602,202
Accumulated amortization	(421,107)	(369,175)
Balance	3,181,095	3,233,027
Technology-Based Intangible Assets [Member]
Cost	1,128,000	1,128,000
Accumulated amortization	(236,661)	(212,250)
Balance	891,339	915,750
Nonsolicitation Agreement [Member]
Cost	28,000	28,000
Accumulated amortization	(28,000)	(28,000)
Balance	$ 0	$ 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
-SubTopic 30
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