CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (84.9)	$ 38.8	$ (132.0)	$ 80.0
Other comprehensive (loss) income, net of tax
Pension and postretirement benefits, net of tax of $(1.1), $(1.0), $(2.2) and $(2.0), respectively	3.6	3.0	7.2	6.0
Net gain (loss) on derivative instruments, net of tax of $(1.6), $6.1, $(4.3) and $(2.4), respectively	4.9	(19.1)	13.2	7.6
Foreign currency translation gain	8.8	7.4	14.5	1.9
Other comprehensive income (loss), net of tax	17.3	(8.7)	34.9	15.5
Comprehensive (loss) income	$ (67.6)	$ 30.1	$ (97.1)	$ 95.5