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Retirement Benefits (Details 5) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Pension Benefits [Member] |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | $ 1,772.2 | $ 2,129.6
Actual returns on plan assets and plan expenses | 248.2 | (107.2)
Employer contributions | 153.4 | 49.3
Effect of currency rates | 2.9 | (5.0)
Benefits paid | (274.6) | (294.5)
Fair value of plan assets at end of year | 1,902.1 | 1,772.2
Other Postretirement Benefits |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0.1 | 0.6
Actual returns on plan assets and plan expenses | 0.0 | (0.5)
Employer contributions | 0.0 | 0.0
Effect of currency rates | 0.0 | 0.0
Benefits paid | 0.0 | 0.0
Fair value of plan assets at end of year | $ 0.1 | $ 0.1

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