Note 7 - Intangible Assets - Schedule of Intangible Assets (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Accumulated amortization	$ (15,162,156)	$ (9,492,947)
Balance	29,654,812
Total, cost	46,627,431	46,525,481
Intangible assets, net	31,465,275	37,032,534
Easements [Member]
Accumulated amortization
Balance	1,810,463	1,088,413
Customer Relationships [Member]
Cost	32,841,900	32,638,900
Accumulated amortization	(13,458,753)	(8,326,564)
Balance	19,383,147	24,312,336
Permits, Licenses and Lease Acquisition Costs [Member]
Cost	9,621,521	9,599,621
Accumulated amortization	(989,964)	(559,285)
Balance	8,631,557	9,040,336
Site Location [Member]
Cost	849,347	849,347
Accumulated amortization	(108,295)	(80,216)
Balance	741,052	769,131
Noncompete Agreements [Member]
Cost	616,000	614,000
Accumulated amortization	(206,727)	(145,517)
Balance	409,273	468,483
Trademarks and Trade Names [Member]
Cost	722,200	722,200
Accumulated amortization	(232,417)	(195,417)
Balance	489,783	526,783
Technology-Based Intangible Assets [Member]
Cost	138,000	138,000
Accumulated amortization	(138,000)	(122,657)
Balance		15,343
Nonsolicitation Agreement [Member]
Cost	28,000	28,000
Accumulated amortization	(28,000)	(28,000)
Balance
Off-Market Favorable Lease [Member]
Cost		847,000
Accumulated amortization		(35,291)
Balance		$ 811,709

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

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