Restructuring and other - Restructuring and Other Costs (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring and other	$ 1.1	$ 4.2	$ 10.3	$ 6.9
Employee severance
Restructuring Cost and Reserve [Line Items]
Restructuring and other	0.0	2.5	2.7	4.8
Acquisitions and related costs
Restructuring Cost and Reserve [Line Items]
Restructuring and other	0.8	0.0	4.2	0.0
Restructuring, integration and other
Restructuring Cost and Reserve [Line Items]
Restructuring and other	$ 0.3	$ 1.7	$ 3.4	$ 2.1