CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 7.0	$ 11.5	$ 0.8	$ 20.4
Other comprehensive income (loss), net of tax
Pension and postretirement benefits, net of tax of $(3.5), $(2.3), $(14.0) and $(4.6), respectively	5.7	3.7	23.1	7.4
Net gain (loss) on derivative instruments, net of tax of $(2.4), $3.4, $(8.8) and $6.8, respectively	3.8	(5.7)	14.6	(11.2)
Foreign currency translation	(4.0)	(2.3)	(4.7)	(5.6)
Other comprehensive income (loss)	5.5	(4.3)	33.0	(9.4)
Comprehensive income	$ 12.5	$ 7.2	$ 33.8	$ 11.0