Pension Plans - Fair Value of Defined Benefit Plan Assets (Details) - Foreign Plan - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	$ 15.5	$ 14.9	$ 13.7
Fair value of defined benefit plan assets		$ 14.8
Asset allocations	100.00%	100.00%
Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	$ 0.0	$ 0.5
Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	3.4	4.1
Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	12.1	10.2	$ 9.0
Equity securities
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	$ 0.0	$ 0.0
Asset allocations	0.00%	0.00%
Equity securities | Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	$ 0.0	$ 0.0
Equity securities | Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	0.0	0.0
Equity securities | Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	0.0	0.0
Debt securities
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	$ 3.1	$ 4.1
Asset allocations	20.00%	28.00%
Debt securities | Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	$ 0.0	$ 0.0
Debt securities | Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	3.1	4.1
Debt securities | Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	0.0	0.0
Insurance arrangements
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	$ 9.6	$ 7.8
Asset allocations	62.00%	53.00%
Insurance arrangements | Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	$ 0.0	$ 0.0
Insurance arrangements | Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	0.0	0.0
Insurance arrangements | Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	9.6	7.8
Cash
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	$ 0.0	$ 0.0
Asset allocations	0.00%	0.00%
Cash | Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	$ 0.0	$ 0.0
Cash | Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	0.0	0.0
Cash | Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	0.0	0.0
Other
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	$ 2.8	$ 2.9
Asset allocations	18.00%	19.00%
Other | Level 1
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	$ 0.0	$ 0.5
Other | Level 2
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	0.3	0.0
Other | Level 3
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of defined benefit plan assets	$ 2.5	$ 2.4