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Note 7 - Stockholders' Equity (Details Textual) $ / shares in Units, $ in Millions	Nov. 22, 2022	Jun. 30, 2025 $ / shares shares	Jun. 30, 2024 $ / shares shares	Jun. 30, 2023 $ / shares	Dec. 21, 2022 $ / shares shares	Nov. 09, 2022 USD ($)
Common Stock, Par or Stated Value Per Share (in dollars per share)		$ 0.001	$ 0.001
Preferred Stock, Shares Issued (in shares) \| shares		280,898	280,898
Share Repurchase Program, Authorized, Amount \| $						$ 1
Preferred Stock, Par or Stated Value Per Share (in dollars per share)		$ 0.001	$ 0.001
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)		69.04	$ 72.1	$ 72.1
Rights Plan [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) \| shares					1
Preferred Stock, Par or Stated Value Per Share (in dollars per share)					$ 0.001
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)					$ 58
Series D Preferred Stock [Member]
Common Stock, Par or Stated Value Per Share (in dollars per share)		$ 0.001
Preferred Stock, Shares Issued (in shares) \| shares		280,898
Reverse Stock Split [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	30