Note 7 - Intangible Assets - Schedule of Intangible Assets (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Accumulated amortization	$ (12,305,583)	$ (9,492,947)
Balance	32,511,385
Total, cost	46,004,381	46,525,481
Intangible assets, net	33,698,798	37,032,534
Easements [Member]
Accumulated amortization
Balance	1,187,413	1,088,413
Customer Relationships [Member]
Cost	32,841,900	32,638,900
Accumulated amortization	(10,885,769)	(8,326,564)
Balance	21,956,131	24,312,336
Permits, Licenses and Lease Acquisition Costs [Member]
Cost	9,621,521	9,599,621
Accumulated amortization	(773,576)	(559,285)
Balance	8,847,945	9,040,336
Site Location [Member]
Cost	849,347	849,347
Accumulated amortization	(94,178)	(80,216)
Balance	755,169	769,131
Noncompete Agreements [Member]
Cost	616,000	614,000
Accumulated amortization	(175,987)	(145,517)
Balance	440,013	468,483
Trademarks and Trade Names [Member]
Cost	722,200	722,200
Accumulated amortization	(213,917)	(195,417)
Balance	508,283	526,783
Technology-Based Intangible Assets [Member]
Cost	138,000	138,000
Accumulated amortization	(134,156)	(122,657)
Balance	3,844	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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