Condensed Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Net Income	$ 14,471	$ 29,011	$ 86,827	$ 91,150
Defined Benefit Pension and Postretirement Benefit Plans:
Prior service credit arising during the period, before tax	0	0	0	2,038
Amortization of loss, before tax	170	124	508	382
Amortization of prior service credit, before tax	(46)	(47)	(136)	(79)
Total Other Comprehensive Income, Before Tax	124	77	372	2,341
Tax Attributes of Items in Other Comprehensive Income:
Prior service credit arising during the period, tax	0	0	0	(753)
Amortization of loss, tax	(63)	(45)	(188)	(142)
Amortization of prior service credit, tax	17	17	50	29
Total Tax Expense	(46)	(28)	(138)	(866)
Other Comprehensive Income, Net of Tax	78	49	234	1,475
Comprehensive Income	$ 14,549	$ 29,060	$ 87,061	$ 92,625