Equity (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Reconciliation of equity attributable to non-controlling interests
NCI, beginning of period	$ (7.2)	$ (11.6)	$ (14.7)	$ (11.5)
Net income (loss) attributable to NCI, net of tax	(1.5)	0.0	45.2	(0.1)
Capital contribution by noncontrolling interest	2.0	0.0	13.1	0.0
Distribution to noncontrolling interest	0.0	0.0	(50.0)	0.0
Translation adjustment and other	(0.1)	0.0	(0.4)	0.0
NCI, end of period	$ (6.8)	$ (11.6)	$ (6.8)	$ (11.6)