Postretirement and Other Benefits (Details) - Pension Benefits - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 0.0	$ 0.0
Interest cost	0.7	0.9
Expected return on plan assets	(1.0)	(1.2)
Amortizations and other	0.9	0.8
Net periodic benefit cost	0.6	0.5
French
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	0.3	0.3
Interest cost	0.0	0.0
Expected return on plan assets	0.0	0.0
Amortizations and other	0.3	0.3
Net periodic benefit cost	$ 0.6	$ 0.6