Other Income, Net (Other Income, Net) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016
Other Income and Expenses [Abstract]
Interest income on corporate funds	$ (10.1)	$ (9.7)	$ (54.5)	$ (45.6)
Realized gains on available-for-sale securities	(0.6)	(2.0)	(3.1)	(3.5)
Realized losses on available-for-sale securities	0.8	2.1	2.0	7.4
Gain on sale of businesses (see Note 4)	0.0		(205.4)
Gain on sale of businesses (see Note 4)		0.0		(29.1)
Gain on sale of building	0.0	0.0	0.0	(13.9)
Other income, net	$ (9.9)	$ (9.6)	$ (261.0)	$ (84.7)