Post Employment Plans - Fair Value of Pension Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	$ 165.4	$ 151.9
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	1.2	1.1
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	108.1	100.9
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	56.1	49.9	$ 50.8
Equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	24.6	16.3
Equities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0.1	0.1
Equities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	24.5	16.2
Equities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0.0	0.0
Bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	33.8	29.6
Bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	1.1	1.0
Bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	32.7	28.6
Bonds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0.0	0.0
Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	56.1	49.9
Insurance contracts | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0.0	0.0
Insurance contracts | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0.0	0.0
Insurance contracts | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	56.1	49.9
Absolute return fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	44.9	50.5
Absolute return fund | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0.0	0.0
Absolute return fund | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	44.9	50.5
Absolute return fund | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0.0	0.0
Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	6.0	5.6
Other | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0.0	0.0
Other | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	6.0	5.6
Other | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets		$ 0.0