CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (40.5)	$ 39.9	$ (172.5)	$ 119.9
Other comprehensive income (loss), net of tax
Pension and postretirement benefits, net of tax of $(31.5), $(0.9), $(33.8) and $(3.1), respectively	98.1	3.1	105.3	9.1
Net gain (loss) on derivative instruments, net of tax of $(0.5), $2.8, $(4.7) and $0.4, respectively	1.7	(8.9)	14.9	(1.3)
Foreign currency translation	(3.7)	(13.2)	10.8	(11.3)
Other comprehensive income (loss), net of tax	96.1	(19.0)	131.0	(3.5)
Comprehensive income (loss)	$ 55.6	$ 20.9	$ (41.5)	$ 116.4