Consolidated Statements Of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock Outstanding [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Treasury Stock [Member]
Balance (in shares) at Jun. 30, 2013		27,324,000
Balance at Jun. 30, 2013	$ 501,222	$ 102,622	$ 1,139,213	$ (8,391)	$ (732,222)
Net income	74,986		74,986
Net pension and postretirement benefit gains (losses), net of tax effect	330			330
Cash dividends - common stock	(46,988)		(46,988)
Purchase of treasury stock (in shares)		(42,000)
Purchase of treasury stock	(3,120)				(3,120)
Stock-based plans, including excess tax benefits (in shares)		57,000
Stock-based plans, including excess tax benefits	(305)	$ (305)
Stock-based compensation expense	2,472	$ 2,472
Balance (in shares) at Jun. 30, 2014		27,339,000
Balance at Jun. 30, 2014	528,597	$ 104,789	1,167,211	(8,061)	(735,342)
Net income	101,686		101,686
Net pension and postretirement benefit gains (losses), net of tax effect	(1,996)			(1,996)
Cash dividends - common stock	(49,778)		(49,778)
Purchase of treasury stock (in shares)		(6,000)
Purchase of treasury stock	(569)				(569)
Stock-based plans, including excess tax benefits (in shares)		28,000
Stock-based plans, including excess tax benefits	(62)	$ (62)
Stock-based compensation expense	$ 3,040	$ 3,040
Balance (in shares) at Jun. 30, 2015	27,360,581	27,361,000
Balance at Jun. 30, 2015	$ 580,918	$ 107,767	1,219,119	(10,057)	(735,911)
Net income	121,764		121,764
Net pension and postretirement benefit gains (losses), net of tax effect	(1,293)			(1,293)
Cash dividends - common stock	(190,546)		(190,546)
Purchase of treasury stock (in shares)		(2,000)
Purchase of treasury stock	(155)				(155)
Stock-based plans, including excess tax benefits (in shares)		65,000
Stock-based plans, including excess tax benefits	(416)	$ (416)
Stock-based compensation expense	$ 3,326	$ 3,326
Balance (in shares) at Jun. 30, 2016	27,423,550	27,424,000
Balance at Jun. 30, 2016	$ 513,598	$ 110,677	$ 1,150,337	$ (11,350)	$ (736,066)