Retirement Benefits - Fair Value Measurements (Details) - Non-U.S. Plans - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 245.5	$ 360.3	$ 355.8
Level 1 | Other plan assets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	88.2	119.0
Level 2 | Other plan assets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	45.3	75.7
Level 3 | Other insurance contract value
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2.7	3.0
Level 3 | Insurance contract - guarantee value
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	75.8	109.7
Fair Value Measured at Net Asset Value Per Share | Other plan assets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 33.5	$ 52.9