Note 9 - Equity Compensation - Stock Options (Details) - USD ($)	12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Outstanding, shares (in shares)		2,300,791
Outstanding, weighted average exercise price (in dollars per share)		$ 6.05
Outstanding, weighted average remaining contractual term (Year)	5 years 4 months 24 days	5 years 8 months 12 days
Outstanding, aggregate intrinsic value	$ 11,705,731	$ 2,287,764
Granted (in shares)	0
Granted, weighted average exercise price (in dollars per share)	$ 0
Exercised (in shares)	(520,566)
Exercised, weighted average exercise price (in dollars per share)	$ 7.12
Forfeited (in shares)	0
Forfeited, weighted average exercise price (in dollars per share)	$ 0
Expired (in shares)	(73,262)
Expired, weighted average exercise price (in dollars per share)	$ 6.58
Outstanding, shares (in shares)	1,706,963
Outstanding, weighted average exercise price (in dollars per share)	$ 5.70
Exercisable, shares (in shares)	1,616,265
Exercisable, weighted average exercise price (in dollars per share)	$ 5.64
Exercisable, weighted average remaining contractual term (Year)	5 years 3 months 18 days
Exercisable, aggregate intrinsic value	$ 11,189,810
Vested and expected to vest, shares (in shares)	1,711,976
Vested and expected to vest at, weighted average exercise price (in dollars per share)	$ 5.71
Vested and expected to vest, weighted average remaining contractual term (Year)	5 years 4 months 24 days
Vested and expected to vest, aggregate intrinsic value	$ 11,734,827