Condensed Consolidated Statements of Stockholders' Equity (Unaudited) (Parentheticals) $ in Thousands	9 Months Ended
	Sep. 30, 2019 USD ($)
May 2019 Public Offering [Member]
Common stock issued during period, offering costs	$ 739
January 2019 Public Offering [Member]
Common stock issued during period, offering costs	$ 1,683