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		6 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014
Accounting Policies [Abstract]
Net income	$ 34,511	$ 32,954	$ 62,139	$ 55,715
Net income available to participating securities	(177)	(57)	(192)	(95)
Net income available to common shareholders	$ 34,334	$ 32,897	$ 61,947	$ 55,620
Weighted average common shares outstanding - basic (in shares)	27,328	27,294	27,324	27,290
Incremental share effect from:
Nonparticipating restricted stock (in shares)	3	3	4	4
Stock-settled stock appreciation rights (in shares)	43	26	31	25
Weighted average common shares outstanding - diluted (in shares)	27,374	27,323	27,359	27,319
Net income per common share - basic (in dollars per share)	$ 1.26	$ 1.21	$ 2.27	$ 2.04
Net income per common share - diluted (in dollars per share)	$ 1.25	$ 1.20	$ 2.26	$ 2.04