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																12 Months Ended
	Jun. 30, 2017		Mar. 31, 2017	[1]	Dec. 31, 2016		Sep. 30, 2016		Jun. 30, 2016		Mar. 31, 2016		Dec. 31, 2015		Sep. 30, 2015		Jun. 30, 2017		Jun. 30, 2016		Jun. 30, 2015
Accounting Policies [Abstract]
Net income	$ 28,487		$ 14,471		$ 38,956		$ 33,400		$ 30,614		$ 29,011		$ 34,511		$ 27,628		$ 115,314	[1]	$ 121,764		$ 101,686
Net income available to participating securities																	(196)		(242)		(143)
Net income available to common shareholders																	$ 115,118		$ 121,522		$ 101,543
Weighted average common shares outstanding - basic (in shares)																	27,376		27,336		27,300
Incremental share effect from:
Nonparticipating restricted stock (in shares)																	3		3		3
Stock-settled stock appreciation rights (in shares)																	61		34		24
Weighted average common shares outstanding - diluted (in shares)																	27,440		27,373		27,327
Net income per common share - basic (in dollars per share)																	$ 4.21		$ 4.45		$ 3.72
Net income per common share - diluted (in dollars per share)	$ 1.04	[2]	$ 0.53	[2]	$ 1.42	[2]	$ 1.22	[2]	$ 1.12	[2]	$ 1.06	[2]	$ 1.25	[2]	$ 1.01	[2]	$ 4.20	[1],[2]	$ 4.44	[2]	$ 3.72

[1] Included in the third quarter and fiscal year net income is expense of $11.5 million, net of taxes, or approximately $0.42 per diluted share, related to a multiemployer pension settlement and other benefit-related costs.

[2] Diluted net income per common share amounts are calculated independently for each of the quarters presented. Accordingly, the sum of the quarterly net income per common share amounts may not agree with the fiscal year.