Pension and Other Postretirement Benefits - Schedule of Projected Benefit Obligations in Excess of Plan Assets and Accumulated Benefit Obligations in Excess of Plan Assets (Details) - USD ($) $ in Millions	Jun. 30, 2024	Jun. 30, 2023
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	$ 678.5	$ 843.8
Fair value of plan assets	471.8	654.8
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	172.8	182.3
Fair value of plan assets	$ 136.3	$ 120.4