Summary Of Significant Accounting Policies (Schedule Of Basic And Diluted Net Income Per Common Share Calculations) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Accounting Policies [Abstract]
Net income	$ 142,332	$ 136,983	$ 150,549
Net income available to participating securities	(285)	(278)	(259)
Net income available to common shareholders	$ 142,047	$ 136,705	$ 150,290
Weighted average common shares outstanding - basic (in shares)	27,475	27,448	27,438
Incremental share effect from:
Nonparticipating restricted stock (in shares)	2	2	2
Stock-settled stock appreciation rights (in shares)	41	46	97
Weighted average common shares outstanding - diluted (in shares)	27,518	27,496	27,537
Net income per common share - basic (in dollars per share)	$ 5.17	$ 4.98	$ 5.48
Net income per common share - diluted (in dollars per share)	$ 5.16	$ 4.97	$ 5.46