Note 12 - Earn-out Milestone Liability - Summary of the Changes in the Earn-out Milestone Liability (Details) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Balance		$ 13,188,226	$ 13,921,412
Non-cash loss from the adjustment for the change in fair value included in net loss	$ (1,200,000)	(649,701)	(733,186)
Balance		$ 12,538,525	$ 13,188,226