Note 2 - Restricted Cash (Details Textual)	3 Months Ended	9 Months Ended
	Mar. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Number of Land Parcels Sold	4
Proceeds from Sale of Property, Plant, and Equipment, Total		$ 996,494	$ 35,474
Restricted Cash and Cash Equivalents, Current, Total	$ 873,355			$ 33,821
Restricted Cash, Total		$ 0
Land [Member]
Proceeds from Sale of Property, Plant, and Equipment, Total	$ 993,160