Benefit Plans and Other Postretirement Benefits, Pension plans with a projected benefit obligation in excess of plan assets (Details) - Pension Benefits - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
United States
Pension Plan with Project Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation	$ 30.1	$ 496.5
Fair value of plan assets	11.7	473.2
Foreign Plans
Pension Plan with Project Benefit Obligation in Excess of Plan Assets [Abstract]
Projected benefit obligation	296.4	261.4
Fair value of plan assets	$ 110.7	$ 107.8