Supplemental Data (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Cost Data:
Repairs and maintenance costs	$ 108.0	$ 99.1	$ 101.8
Noncash investing and financing activities:
Sale of equity method investment	0.0	0.0	12.6
Noncash purchases of property, equipment and software	16.5	13.7	15.1
Cash paid (received) during the year for:
Interest payments, net	29.5	27.7	27.5
Income tax payments (refunds), net	$ 33.7	$ (33.3)	$ 27.9