Note 11 - Stock-based Compensation - Stock Options Outstanding (Details)	6 Months Ended
	Dec. 31, 2023 $ / shares shares
Outstanding, exercise prices range lower limit (in dollars per share)	$ 10.1
Outstanding, exercise prices range upper (in dollars per share)	$ 175.5
Number outstanding (in shares) | shares	154,910
Weighted average remaining contractual lifeWeighted average remaining contractual life (Year)	9 years 3 months 29 days
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 14.36
Shares Exercisable (in shares) | shares	13,559
Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 44.35
Exercise Price Range 1 [Member]
Outstanding, exercise prices range lower limit (in dollars per share)	10.1
Outstanding, exercise prices range upper (in dollars per share)	$ 19.2
Number outstanding (in shares) | shares	152,285
Weighted average remaining contractual lifeWeighted average remaining contractual life (Year)	9 years 5 months 4 days
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 11.99
Shares Exercisable (in shares) | shares	10,934
Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 18.54
Exercise Price Range 2 [Member]
Outstanding, exercise prices range lower limit (in dollars per share)	55.5
Outstanding, exercise prices range upper (in dollars per share)	$ 84.9
Number outstanding (in shares) | shares	418
Weighted average remaining contractual lifeWeighted average remaining contractual life (Year)	4 years 10 months 13 days
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 61.52
Shares Exercisable (in shares) | shares	418
Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 61.52
Exercise Price Range 3 [Member]
Outstanding, exercise prices range lower limit (in dollars per share)	159
Outstanding, exercise prices range upper (in dollars per share)	$ 175.5
Number outstanding (in shares) | shares	2,207
Weighted average remaining contractual lifeWeighted average remaining contractual life (Year)	3 years 4 months 9 days
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 168.97
Shares Exercisable (in shares) | shares	2,207
Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 168.97