Employee Benefit Plans UK Pension Assets, Fair Value Measurement by Input Level (Details) - Pension Plan - UNITED KINGDOM - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Diversified Growth Assets
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	$ 40.6	$ 157.3
Diversified Growth Assets | Fair Value, Inputs, Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	32.3	113.1
Diversified Growth Assets | Fair Value, Inputs, Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Diversified Growth Assets | Fair Value, Inputs, Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Diversified Growth Assets | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	8.3	44.2
Fixed Income and Index-linked Securities
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	70.6	124.1
Fixed Income and Index-linked Securities | Fair Value, Inputs, Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	70.6	124.1
Fixed Income and Index-linked Securities | Fair Value, Inputs, Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Fixed Income and Index-linked Securities | Fair Value, Inputs, Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Fixed Income and Index-linked Securities | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Alternative Investments
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	28.1	18.2
Alternative Investments | Fair Value, Inputs, Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Alternative Investments | Fair Value, Inputs, Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Alternative Investments | Fair Value, Inputs, Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Alternative Investments | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	28.1	18.2
Cash Equivalents
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	1.9	4.1
Cash Equivalents | Fair Value, Inputs, Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	1.9	4.1
Cash Equivalents | Fair Value, Inputs, Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Cash Equivalents | Fair Value, Inputs, Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Cash Equivalents | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Total Invested Assets
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	141.2	303.7
Total Invested Assets | Fair Value, Inputs, Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	104.8	241.3
Total Invested Assets | Fair Value, Inputs, Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Total Invested Assets | Fair Value, Inputs, Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	0.0	0.0
Total Invested Assets | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans and Other Postretirement Benefit Plans
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Amount	$ 36.4	$ 62.4