Note 8 - Stockholders' Equity - Schedule of Warrant Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2022
Outstanding (in shares)	80	80
Warrants Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 72.1	$ 72.1
Outstanding, Aggregate Fair Market Value	$ 3,747	$ 3,747	$ 3,747
Outstanding, Weighted Average Remaining Contractual Term (Year)	1 year 7 months 6 days	2 years 7 months 6 days	3 years 7 months 6 days
Issued (in shares)		0
Warrants Issued (in dollars per share)		$ 0
Issued		$ 0
Outstanding (in shares)	80	80	80
Warrants Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 72.1	$ 72.1	$ 72.1
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 72.1	$ 72.1	$ 72.1
Outstanding (in shares)	80	80	80
Class of Warrant or Rights, Warrants Issued March 26, 2020 [Member]
Outstanding (in shares)	1
Outstanding (in shares)	1	1
Warrants Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 187.5
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 187.5
Class Of Warrant Or Right, Expiration Date	Mar. 25, 2025
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
Warrants Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 140.63
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 140.63
Class Of Warrant Or Right, Expiration Date	Mar. 27, 2025
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
Warrants Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 86.25
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 86.25
Class Of Warrant Or Right, Expiration Date	Oct. 21, 2025
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
Warrants Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 80.63
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 80.63
Class Of Warrant Or Right, Expiration Date	Oct. 28, 2025
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
Warrants Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 121.88
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 121.88
Class Of Warrant Or Right, Expiration Date	Feb. 11, 2026
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
Warrants Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 56.25
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 56.25
Class Of Warrant Or Right, Expiration Date	Apr. 07, 2026
Outstanding (in shares)	50	50