Restructuring Charges - Activity and Reserve Balance for Restructuring Charges by Segment (Details) - USD ($) $ in Millions	6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	$ 4.0	$ 8.1	$ 8.1
Restructuring charges	14.0		7.3
Adjustments to estimates on restructuring reserves	(0.3)	(1.1)	(1.6)
Cash payments	(14.9)		(9.8)
Restructuring reserve, ending balance	2.8		4.0
Americas
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	0.9	1.6	1.6
Restructuring charges	12.4		1.8
Adjustments to estimates on restructuring reserves	0.0		(0.5)
Cash payments	(12.9)		(2.0)
Restructuring reserve, ending balance	0.4		0.9
International
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	2.8	5.4	5.4
Restructuring charges	1.6		5.3
Adjustments to estimates on restructuring reserves	(0.3)		(0.6)
Cash payments	(1.7)		(7.3)
Restructuring reserve, ending balance	2.4		2.8
Corporate
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	0.3	$ 1.1	1.1
Restructuring charges	0.0		0.2
Adjustments to estimates on restructuring reserves	0.0		(0.5)
Cash payments	(0.3)		(0.5)
Restructuring reserve, ending balance	$ 0.0		$ 0.3