Pension and Other Postretirement Benefits - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020	Jun. 30, 2020
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Settlement charge	$ 8.9	$ 0.0	$ 8.9	$ 0.0
Defined benefit plan, assumptions used calculation benefit obligation, discount rate	3.21%		3.21%		3.02%
Defined benefit plan, benefit obligation, (increase) decrease for premeasurement due to settlement	$ 3.1
Pension expense (reversal of expense), noncash	0.8
Liability, defined benefit pension plan	116.7		$ 116.7
Pension Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Settlement charge	8.9	$ 0.0	8.9	0.0
Contributions			10.9	$ 4.9
Expected contributions expected during the remainder of fiscal year	$ 9.0		$ 9.0