Service Alignment Initiative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		18 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Restructuring Reserve [Roll Forward]
Beginning balance			$ 74.4	$ 0.0	$ 0.0
Charged to expense	$ 13.1	$ 0.6	26.0	41.6
Reversals			(12.9)	0.0
Restructuring charges, net of reversals			13.1	41.6
Cumulative amount from inception through					103.1
Cash payments			(29.3)	(7.3)
Non-cash utilization			(0.7)	(1.6)
Ending balance	57.5	32.7	57.5	32.7
Employee separation benefits
Restructuring Reserve [Roll Forward]
Beginning balance			73.9	0.0	0.0
Charged to expense	11.8	(0.1)	21.8	37.2
Reversals			(12.9)	0.0
Restructuring charges, net of reversals			8.9	37.2
Cumulative amount from inception through					93.0
Cash payments			(25.9)	(4.9)
Non-cash utilization			0.0	0.0
Ending balance	56.9	32.3	56.9	32.3
Other initiative costs
Restructuring Reserve [Roll Forward]
Beginning balance			0.5	0.0	0.0
Charged to expense	1.3	0.7	4.2	4.4
Reversals			0.0	0.0
Cumulative amount from inception through					$ 10.1
Cash payments			(3.4)	(2.4)
Non-cash utilization			(0.7)	(1.6)
Ending balance	0.6	$ 0.4	0.6	$ 0.4
Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 7.0		$ 7.0