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	3 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Accounting Policies [Abstract]
Net income	$ 30,655	$ 37,079
Net income available to participating securities	(87)	(79)
Net income available to common shareholders	$ 30,568	$ 37,000
Weighted average common shares outstanding - basic (in shares)	27,459	27,461
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incremental share effect from stock-settled stock appreciation rights (in shares)	49	31
Diluted (in shares)	27,515	27,495
Net income per common share - basic and diluted (in dollars per share)	$ 1.11	$ 1.35
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)	3	3
Performance units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incremental share effect from awards with forfeitable dividends (in shares)	4	0

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