Note 7 - Intangible Assets - Schedule of Intangible Assets (Details) - USD ($)	Jun. 30, 2021	Dec. 31, 2020
Accumulated amortization	$ (26,531,597)	$ (24,160,885)
Balance	40,114,107
Total, cost	71,152,793	68,534,794
Intangible assets, net	44,621,196	44,373,909
Easements [Member]
Accumulated amortization	0	0
Balance	4,507,089	4,507,089
Customer Relationships [Member]
Cost	48,883,484	46,740,483
Accumulated amortization	(22,180,979)	(20,558,751)
Balance	26,702,505	26,181,732
Permits, Licenses and Lease Acquisition Costs [Member]
Cost	11,278,673	11,053,673
Accumulated amortization	(2,923,192)	(2,412,313)
Balance	8,355,481	8,641,360
Site Location [Member]
Cost	849,347	849,347
Accumulated amortization	(221,541)	(193,462)
Balance	627,806	655,885
Noncompete Agreements [Member]
Cost	626,000	626,000
Accumulated amortization	(439,638)	(386,934)
Balance	186,362	239,066
Technology-Based Intangible Assets [Member]
Cost	1,128,000	1,128,000
Accumulated amortization	(261,343)	(212,250)
Balance	866,657	915,750
Trademarks and Trade Names [Member]
Cost	3,852,200	3,602,202
Accumulated amortization	(476,904)	(369,175)
Balance	3,375,296	3,233,027
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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-Name Accounting Standards Codification
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