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, 2023	Jun. 30, 2022	Jun. 30, 2021
Accounting Policies [Abstract]
Net income	$ 111,286	$ 89,586	$ 142,332
Net income available to participating securities	(257)	(224)	(285)
Net income available to common shareholders	$ 111,029	$ 89,362	$ 142,047
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average common shares outstanding - basic (in shares)	27,462	27,448	27,475
Weighted average common shares outstanding - diluted (in shares)	27,482	27,472	27,518
Net income per common share - basic (in dollars per share)	$ 4.04	$ 3.26	$ 5.17
Net income per common share - diluted (in dollars per share)	$ 4.04	$ 3.25	$ 5.16
Nonparticipating Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incremental share effect from awards with forfeitable dividends (in shares)	2	2	2
Stock Settled Stock Appreciation Rights SARS [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incremental share effect from stock-settled stock appreciation rights (in shares)	15	21	41
Weighted average number of antidilutive securities (in rights outstanding)	100	300	100
Performance Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incremental share effect from awards with forfeitable dividends (in shares)	3	1	0