Noncontrolling Interests (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Noncontrolling interests
Balance at beginning of period	$ 7.4	$ 7.1	$ 6.7	$ 6.8
Net income	0.6	0.5	1.3	0.8
Foreign currency translation adjustments	0.1	0.1	0.6	0.1
Cash payments to noncontrolling interest		(0.7)	(0.5)	(0.7)
Balance at end of period	$ 8.1	$ 7.0	$ 8.1	$ 7.0