Employee Benefit Plans UK Pension Assets, Fair Value Measurement by Input Level (Details) - Pension Plan - UNITED KINGDOM - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	$ 303.7	$ 294.1	$ 252.8
Fair Value, Inputs, Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	241.3	118.1
Fair Value, Inputs, Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	0.0	0.0
Fair Value, Inputs, Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	0.0	0.0
Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	62.4	176.0
Diversified Growth Assets
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	157.3	176.0
Diversified Growth Assets | Fair Value, Inputs, Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	113.1	0.0
Diversified Growth Assets | Fair Value, Inputs, Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	0.0	0.0
Diversified Growth Assets | Fair Value, Inputs, Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	0.0	0.0
Diversified Growth Assets | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	44.2	176.0
Fixed Interest and Index-linked Securities
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	124.1	116.8
Fixed Interest and Index-linked Securities | Fair Value, Inputs, Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	124.1	116.8
Fixed Interest and Index-linked Securities | Fair Value, Inputs, Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	0.0	0.0
Fixed Interest and Index-linked Securities | Fair Value, Inputs, Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	0.0	0.0
Fixed Interest and Index-linked Securities | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	0.0	0.0
Alternative Investments
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	18.2
Alternative Investments | Fair Value, Inputs, Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	0.0
Alternative Investments | Fair Value, Inputs, Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	0.0
Alternative Investments | Fair Value, Inputs, Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	0.0
Alternative Investments | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	18.2
Cash Equivalents
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	4.1	1.3
Cash Equivalents | Fair Value, Inputs, Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	4.1	1.3
Cash Equivalents | Fair Value, Inputs, Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	0.0	0.0
Cash Equivalents | Fair Value, Inputs, Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	0.0	0.0
Cash Equivalents | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plans and Other Postretirement Benefit Plans
Fair Value of Plan Assets	$ 0.0	$ 0.0