Condensed Consolidated Statements Of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Condensed Consolidated Statements Of Comprehensive Income [Abstract]
Net Income	$ 21,833	$ 18,222	$ 83,772	$ 69,853
Defined Benefit Pension and Postretirement Benefit Plans:
Amortization of loss, before tax	166	81	500	243
Amortization of prior service asset, before tax	(1)	(1)	(3)	(3)
Total Other Comprehensive Income, Before Tax	165	80	497	240
Amortization of loss, tax	(62)	(30)	(186)	(91)
Amortization of prior service asset, tax	1	1	1	1
Total Other Comprehensive Income, Tax	(61)	(29)	(185)	(90)
Other Comprehensive Income, Net of Tax	104	51	312	150
Comprehensive Income	$ 21,937	$ 18,273	$ 84,084	$ 70,003