Note 2 - Earnings per Common Share - Basic and Diluted Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Net income	$ 9,646	$ 22,502	$ 47,871
Basic earnings per common share - weighted-average shares (in shares)	81,350	81,210
Effect of dilutive stock options (in shares)	87	166
Diluted earnings per common share - weighted-average shares and assumed conversions (in shares)	81,437	81,376
Basic earnings per common share (in dollars per share)	$ 0.12	$ 0.28
Diluted earnings per common share (in dollars per share)	$ 0.12	$ 0.28