Pension Benefit Plans (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Retirement Benefits [Abstract]
Service cost	$ 1.5	$ 1.4	$ 4.6	$ 4.2
Interest cost	1.0	1.6	4.1	5.0
Expected return on plan assets	(1.7)	(2.0)	(7.1)	(6.2)
Amortization of prior service cost	0.1	0.0	0.1	0.1
Recognized actuarial loss	1.8	1.4	6.0	4.3
Other	0.0	0.1	(0.4)	0.0
Settlements and curtailments	0.3	0.3	1.1	0.3
Net periodic benefit cost	$ 3.0	$ 2.8	$ 8.4	$ 7.7