Long-term Employee Benefits - Schedule of Net Benefit Cost (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Net periodic benefit cost:
Service cost	$ 2.2	$ 2.4	$ 6.4	$ 7.5
Interest cost	3.3	3.7	10.0	11.5
Expected return on plan assets	(3.7)	(3.0)	(10.7)	(9.6)
Amortization of actuarial loss, net	0.3	0.1	1.1	0.2
Net periodic benefit (gain) cost	$ 2.1	$ 3.2	$ 6.8	$ 9.6