Restructuring Accrual - Changes in Restructuring Accrual (Details) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Mar. 31, 2018
Restructuring Reserve [Roll Forward]
Balance at beginning of period	$ 107.6
Accruals	22.6
Cash payments	(30.1)
Other accruals	(0.5)
Reversal of excess accrual	(3.6)
Balance at end of period	96.0
Restructuring liability, current portion	91.4		$ 91.4
Restructuring liability, noncurrent portion	4.6		$ 4.6
Employee Terminations
Restructuring Reserve [Roll Forward]
Balance at beginning of period	101.3	$ 8.7
Accruals	12.5	0.0
Cash payments	(20.7)	(3.0)
Other accruals	(0.5)	0.0
Reversal of excess accrual	(2.9)	0.0
Balance at end of period	89.7	$ 5.7
Other Exit Costs
Restructuring Reserve [Roll Forward]
Balance at beginning of period	6.3
Accruals	10.1
Cash payments	(9.4)
Other accruals	0.0
Reversal of excess accrual	(0.7)
Balance at end of period	$ 6.3