Earnings Per Share - Computation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share [Abstract]
Net income	$ 115,350	$ 100,742	$ 285,267	$ 276,968
Weighted-average number of basic shares outstanding during the period (in shares)	22,292	23,055	22,407	23,329
Dilutive effect of RSUs after application of treasury stock method (in shares)	186	222	186	217
Weighted-average number of diluted shares outstanding during the period (in shares)	22,478	23,277	22,593	23,546
Basic earnings per share (in dollars per shares)	$ 5.17	$ 4.37	$ 12.73	$ 11.87
Diluted earnings per share (in dollars per shares)	$ 5.13	$ 4.33	$ 12.63	$ 11.76