Shareholders' Equity - Components of Accumulated Other Comprehensive Loss, Net of Tax (Details) - USD ($) $ in Millions	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	$ 2,542.8	$ 2,639.0	$ 2,761.5	$ 2,694.5	$ 2,649.9	$ 2,698.5
Foreign currency translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	(308.1)		(260.5)
Translation gain on derivative instruments, net of income taxes of $(9.0) and $(9.1), respectively
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	14.5		13.1
Translation loss on long-term intercompany loans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	(121.9)		(121.5)
Defined benefit pension plans and Retiree health care plan | Defined benefit pension plans, net of income taxes of $(35.2) and $(30.9), respectively
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	(65.3)		(74.1)
Defined benefit pension plans and Retiree health care plan | Retiree health care plan, net of income taxes of $2.2 and $1.6, respectively
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	1.7		2.0
Accumulated other comprehensive loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	$ (479.1)	$ (505.8)	$ (441.0)	$ (416.5)	$ (401.8)	$ (399.8)