Note 11 - Net Income (Loss) Per Share - Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						6 Months Ended		9 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Net loss	$ 7,311	$ (12,522)	$ (4,955)	$ (5,162)	$ (680)	$ (430)	$ (10,166)	$ (6,272)	$ (10,166)	$ (6,272)
Change in warrant derivative liability	(18)								(18)
Dividends on convertible preferred stock	(78)			(79)					(235)	(231)
Net income/(loss) applicable to common shareholders	$ 7,233			$ (5,241)					$ (10,401)	$ (6,503)
Weighted average shares outstanding for basic earnings per share (in shares)	1,996,326			84,825					839,975	84,457
Warrants (in shares)	1,000								1,000
Preferred stock (in shares)	36,000
Adjusted weighted-average shares outstanding and assumed conversions for diluted earnings per share (in shares)	2,032,766			84,825					839,975	84,457
Basic net income/(loss) per share (in dollars per share)	$ 3.62			$ (61.78)					$ (12.38)	$ (77)
Diluted net income/(loss) per share (in dollars per share)	$ 3.56			$ (61.78)					$ (12.38)	$ (77)