Components of Deferred Tax Assets (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Deferred Tax Assets, Net [Abstract]
Postretirement/post-employment benefits	$ 16.7	$ 17.9
Deferred compensation	99.5	99.8
Pension costs	23.7	22.2
Basis differences in fixed assets	(75.3)	(71.7)
Rent	0.0	27.3
Interest	45.5	48.8
Accruals and reserves	19.4	21.0
Allowance for doubtful accounts	6.5	7.4
Basis differences in intangible assets	(321.0)	(302.7)
Deferred Tax Assets, Investments	0.3	1.2
Deferred Tax Liabilities, ROU	335.2	0.0
Deferred Tax Liabilities, Leasing Arrangements	361.4	0.0
Tax loss/tax credit carry forwards	297.1	345.6
Prepaid expenses	(6.7)	(6.3)
Deferred revenue	(21.7)	(26.8)
Unremitted foreign earnings	(1.3)	(9.5)
Other	44.5	38.2
Net deferred tax assets	153.4	212.4
Valuation allowance	(164.2)	(211.0)	$ (243.0)	$ (255.6)
Total deferred tax assets, net	$ (10.8)	$ 1.4