Retirement Benefits - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($) benefit_plan	Dec. 31, 2021 USD ($) benefit_plan	Dec. 31, 2020 USD ($) benefit_plan	Dec. 31, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Number of defined contribution pension plans | benefit_plan	4
Defined contribution pension plans, total costs	$ 25.8	$ 23.3	$ 21.0
Number of multiemployer defined benefit pension plans | benefit_plan	1	1	1
Multiemployer plan total employer contributions	$ 0.2	$ 0.2	$ 0.2
Futures contract supported by cash or cash equivalents	100.00%
United States
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.50%	2.90%
United Kingdom
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.00%	1.80%
Canada
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.01%	2.98%
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation	$ 670.8	$ 937.7	994.2
Settlement losses	8.8	0.0	7.5
Employer contributions	$ 19.8	7.9
Settlement of multi-employer pension plan		$ 5.0	$ 6.0
Discount rate	5.46%	2.79%	2.47%
Pension Benefits | Continuing Operations
Defined Benefit Plan Disclosure [Line Items]
Settlement losses	$ 7.0
Pension Benefits | Discontinued Operations
Defined Benefit Plan Disclosure [Line Items]
Settlement losses	$ 1.8
Pension Benefits | United States
Defined Benefit Plan Disclosure [Line Items]
Curtailment loss				$ 0.3
Defined benefit obligation per plan, as a percent of total benefit obligation	90.00%
Pension Benefits | Qualified Plan | United States
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 10.0	$ 0.0
Pension Benefits | Qualified Plan | United Kingdom
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	2.5
Company Stock
Defined Benefit Plan Disclosure [Line Items]
Employer stock included in plan assets	$ 0.0	$ 0.0