Pension and Other Benefits Additional Information (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined benefit plan, benefit obligation, payment for settlement	$ 1.2
Liability, defined benefit pension plan	74.3
Settlement charge	$ 31.3
Pension Plan
Settlement charge			$ (31.3)
Defined benefit plan, funded (unfunded) status of plan		$ (73.9)	$ (76.8)
Defined benefit plan, required future payment, next twelve months		0.0
Defined benefit plan, expected future employer contributions, next fiscal year		$ 4.0
Defined benefit plan, assumptions used calculating net periodic benefit cost, discount rate		3.23%	3.57%	3.58%
Defined benefit plan, pension plan with accumulated benefit obligation in excess of plan assets, projected benefit obligation		$ 51.5	$ 49.2
Defined benefit plan, plan with accumulated benefit obligation in excess of plan assets, accumulated benefit obligation		51.5	49.2
Defined benefit plan, plan with accumulated benefit obligation in excess of plan assets, plan assets		46.2	40.5
Pension Plan 1
Defined benefit plan, funded (unfunded) status of plan		5.3	8.9
Defined benefit plan, expected future benefit payment, next twelve months			8.5
Supplemental Employee Retirement Plan
Defined benefit plan, funded (unfunded) status of plan		$ 68.6	$ 67.9
Defined benefit plan, assumptions used calculating net periodic benefit cost, discount rate		3.18%	4.32%	3.65%
Defined benefit plan, pension plan with accumulated benefit obligation in excess of plan assets, projected benefit obligation		$ 68.6	$ 67.9
Defined benefit plan, plan with accumulated benefit obligation in excess of plan assets, accumulated benefit obligation		68.6	67.9
Defined benefit plan, plan with accumulated benefit obligation in excess of plan assets, plan assets		0.0	0.0
SERP and Postretirement Benefits
Defined benefit plan, expected future benefit payment, next twelve months		5.7
Deferred Compensation, Excluding Share-based Payments and Retirement Benefits
Defined contribution plan, cost		3.7	4.5	$ 4.4
Contribution expense related to international benefit plans		2.0	1.6	$ 2.5
Other Postretirement Benefits Plan
Settlement charge			0.0
Defined benefit plan, funded (unfunded) status of plan		(0.6)	$ (0.7)
Defined benefit plan, expected future benefit payment, next twelve months		$ 0.0
Defined benefit plan, assumptions used calculating net periodic benefit cost, discount rate		3.33%	4.41%	3.72%
Defined benefit plan, pension plan with accumulated benefit obligation in excess of plan assets, projected benefit obligation		$ 0.6	$ 0.7
Defined benefit plan, plan with accumulated benefit obligation in excess of plan assets, accumulated benefit obligation		0.0	0.0
Defined benefit plan, plan with accumulated benefit obligation in excess of plan assets, plan assets		$ 0.0	$ 0.0