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						9 Months Ended
	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Mar. 31, 2024	Mar. 31, 2023
Accounting Policies [Abstract]
Net income	$ 28,350	$ 51,484	$ 43,951	$ 24,555	$ 39,973	$ 37,592	$ 123,785	$ 102,120
Net income available to participating securities	(65)			(43)			(333)	(246)
Net income available to common shareholders	$ 28,285			$ 24,512			$ 123,452	$ 101,874
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average common shares outstanding - basic (in shares)	27,436			27,465			27,437	27,462
Weighted average common shares outstanding - diluted (in shares)	27,451			27,487			27,455	27,479
Net income per common share - basic (in dollars per share)	$ 1.03			$ 0.89			$ 4.50	$ 3.71
Net income per common share - diluted (in dollars per share)	$ 1.03			$ 0.89			$ 4.50	$ 3.71
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			1			3	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)	4			19			7	12
Weighted average number of antidilutive securities (in rights outstanding)							100	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)	9			2			8	3