Note 7 - Intangible Assets - Schedule of Intangible Assets (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Accumulated amortization	$ (6,513,762)	$ (3,456,290)
Balance	39,501,306
Total, cost	46,956,481	12,805,913
Intangible assets, net	40,442,719	9,349,623
Easements [Member]
Accumulated amortization
Balance	941,413	466,360
Customer Relationships [Member]
Cost	32,638,900	8,132,900
Accumulated amortization	(5,652,893)	(2,970,533)
Balance	26,986,007	5,162,367
Permits, Licenses and Lease Acquisition Costs [Member]
Cost	9,599,621	2,184,106
Accumulated amortization	(340,166)	(178,835)
Balance	9,259,455	2,005,271
Site Location [Member]
Cost	849,347	849,347
Accumulated amortization	(66,060)	(23,593)
Balance	783,287	825,754
Noncompete Agreements [Member]
Cost	614,000	285,000
Accumulated amortization	(114,817)	(66,417)
Balance	499,183	218,583
Trademarks and Trade Names [Member]
Cost	722,200	722,200
Accumulated amortization	(176,917)	(112,250)
Balance	545,283	609,950
Technology-Based Intangible Assets [Member]
Cost	138,000	138,000
Accumulated amortization	(111,159)	(76,662)
Balance	26,841	61,338
Nonsolicitation Agreement [Member]
Cost	28,000	28,000
Accumulated amortization	(28,000)	(28,000)
Balance
Off-Market Favorable Lease [Member]
Cost	1,425,000
Accumulated amortization	(23,750)
Balance	$ 1,401,250

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