Note 5 - Stockholders' Equity - Schedule of Warrant Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2022	Jun. 30, 2022
Outstanding (in shares)	80
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 72.10
Outstanding, Aggregate Fair Market Value	$ 3,747	$ 3,747
Outstanding, Weighted Average Remaining Contractual Term (Year)	3 years 1 month 6 days	3 years 7 months 6 days
Warrants issued (in shares)	0
Warrants issued, Weighted Average Exercise Price (in dollars per share)	$ 0
Warrants issued, Aggregate Fair Market Value	$ 0
Warrants exercised (in shares)	0
Warrants exercised, Weighted Average Exercise Price (in dollars per share)	$ 0
Warrants exercised, Aggregate Fair Market Value	$ 0
Warrants expired (in shares)	0
Warrants expired,Weighted Average Exercise Price (in dollars per share)	$ 0
Warrants expired, Aggregate Fair Market Value	$ 0
Outstanding (in shares)	80	80
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 72.10	$ 72.10
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 72.10	$ 72.10
Outstanding (in shares)	80	80
Class of Warrant or Rights, Warrants Issued March 26, 2020 [Member]
Outstanding (in shares)	1
Outstanding (in shares)	1	1
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 187.50
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 187.50
Outstanding (in shares)	1	1
Class of Warrant or Rights, Warrants Issued March 30, 2020 [Member]
Outstanding (in shares)	2
Outstanding (in shares)	2	2
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 140.63
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 140.63
Outstanding (in shares)	2	2
Class of Warrant or Rights, Warrants Issued October 23, 2020 [Member]
Outstanding (in shares)	15
Outstanding (in shares)	15	15
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 86.25
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 86.25
Outstanding (in shares)	15	15
Class of Warrant or Rights, Warrants Issued October 28, 2020 [Member]
Outstanding (in shares)	6
Outstanding (in shares)	6	6
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 80.63
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 80.63
Outstanding (in shares)	6	6
Class of Warrant or Rights, Warrants Issued February 16, 2021 [Member]
Outstanding (in shares)	6
Outstanding (in shares)	6	6
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 121.88
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 121.88
Outstanding (in shares)	6	6
Class of Warrant or Rights, Warrants Issued April 12, 2021 [Member]
Outstanding (in shares)	50
Outstanding (in shares)	50	50
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 56.25
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 56.25
Outstanding (in shares)	50	50