Note 5 - Stockholders' Equity - Schedule of Warrant Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended	12 Months Ended
	Mar. 21, 2022	Jun. 30, 2021	Mar. 31, 2022
Outstanding (in shares)	2,393
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 2.40
Outstanding, Aggregate Fair Market Value	$ 3,747	$ 3,747
Outstanding, Weighted Average Remaining Contractual Term (Year)	3 years 10 months 6 days	4 years 7 months 17 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)	2,393	2,393
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 2.40	$ 2.40
Class Of Warrant Or Right, Exercise Price (in dollars per share)	$ 2.40	$ 2.40
Class Of Warrant Or Right, Outstanding (in shares)	2,393	2,393	2,393
Class of Warrant or Rights, Warrants Issued March 26, 2020 [Member]
Outstanding (in shares)	25
Outstanding (in shares)		25
Class Of Warrant Or Right, Exercise Price (in dollars per share)			$ 6.25
Class Of Warrant Or Right, Expiration Date			Mar. 25, 2025
Class Of Warrant Or Right, Outstanding (in shares)		25	25
Class of Warrant or Rights, Warrants Issued March 30, 2020 [Member]
Outstanding (in shares)	61
Outstanding (in shares)		61
Class Of Warrant Or Right, Exercise Price (in dollars per share)			$ 4.69
Class Of Warrant Or Right, Expiration Date			Mar. 27, 2025
Class Of Warrant Or Right, Outstanding (in shares)		61	61
Class of Warrant or Rights, Warrants Issued October 23, 2020 [Member]
Outstanding (in shares)	470
Outstanding (in shares)		470
Class Of Warrant Or Right, Exercise Price (in dollars per share)			$ 2.88
Class Of Warrant Or Right, Expiration Date			Oct. 21, 2025
Class Of Warrant Or Right, Outstanding (in shares)		470	470
Class of Warrant or Rights, Warrants Issued October 28, 2020 [Member]
Outstanding (in shares)	173
Outstanding (in shares)		173
Class Of Warrant Or Right, Exercise Price (in dollars per share)			$ 2.69
Class Of Warrant Or Right, Expiration Date			Oct. 28, 2025
Class Of Warrant Or Right, Outstanding (in shares)		173	173
Class of Warrant or Rights, Warrants Issued February 16, 2021 [Member]
Outstanding (in shares)	171
Outstanding (in shares)		171
Class Of Warrant Or Right, Exercise Price (in dollars per share)			$ 4.06
Class Of Warrant Or Right, Expiration Date			Feb. 11, 2026
Class Of Warrant Or Right, Outstanding (in shares)		171	171
Class of Warrant or Rights, Warrants Issued April 12, 2021 [Member]
Outstanding (in shares)	1,493
Outstanding (in shares)		1,493
Class Of Warrant Or Right, Exercise Price (in dollars per share)			$ 1.88
Class Of Warrant Or Right, Expiration Date			Apr. 07, 2026
Class Of Warrant Or Right, Outstanding (in shares)		1,493	1,493