Post Employment Plans - Fair Value of Pension Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jun. 27, 2015
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	$ 162.5	$ 138.2	$ 126.7
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	1.9	1.7
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	109.8	93.1	91.5
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	50.8	43.4	35.2	$ 34.3
Equities
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	19.2	13.7	14.5
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	19.1	13.6	14.5
Equities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0.0	0.0	0.0
Bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	32.0	24.4	38.1
Bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	1.8	1.6
Bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	30.2	22.8	38.1
Bonds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0.0	0.0	0.0
Property
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0.3
Property | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0.0
Property | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets			0.3
Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	50.8	43.4	34.9
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	0.0
Insurance contracts | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	50.8	43.4	34.9
Absolute return fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	54.5	51.5	33.7
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	54.5	51.5	33.7
Absolute return fund | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	0.0	0.0	0.0
Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	6.0	5.2	5.2
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	5.2	5.2
Other | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets	$ 0.0	$ 0.0	$ 0.0