Employee Benefit Plans (Details) - Defined Benefit Plans - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2021	Jun. 30, 2020
Components of net periodic benefit cost
Service cost	$ 0.7	$ 0.7		$ 1.4	$ 1.4
Interest cost	0.7	1.2		1.4	2.3
Expected return on plan assets	(2.5)	(2.5)		(4.9)	(4.9)
Amortization of unrecognized loss	1.6	1.3		3.2	2.7
Settlement expense	0.5	0.0		0.9	0.0
Net periodic benefit cost	1.0	$ 0.7		2.0	1.5
Amortization of unrecognized actuarial loss, provision for income tax	$ (0.4)		$ (0.3)	$ (0.8)	$ (0.6)