Supplemental Data (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Cost Data:
Repairs and maintenance costs	$ 117.4	$ 120.4	$ 108.0
Noncash investing and financing activities:
Noncash purchases of property, plant, equipment and software	11.6	16.1	16.5
Cash paid during the year for:
Interest payments, net	27.0	27.6	29.5
Income tax payments (refunds), net	$ 29.8	$ 27.5	$ 33.7