Property, Equipment And Software (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, Equipment and Software, Gross	$ 1,569.9	$ 1,502.7
Less: Accumulated Depreciation	(1,001.7)	(919.2)
Less: Impairment Expense	(4.4)	0.0
Property, Equipment and Software, Net	563.8	583.5
Impairment expense	17.8
Impairment expense related to right-of-use asset	13.4
Depreciation expense	141.0	124.9	$ 112.4
Technology and Other Equipment
Property, Plant and Equipment [Line Items]
Property, Equipment and Software, Gross	302.4	310.5
Software
Property, Plant and Equipment [Line Items]
Property, Equipment and Software, Gross	810.7	733.4
Land and Buildings
Property, Plant and Equipment [Line Items]
Property, Equipment and Software, Gross	119.0	110.3
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property, Equipment and Software, Gross	254.7	274.1
Work in Process
Property, Plant and Equipment [Line Items]
Property, Equipment and Software, Gross	$ 83.1	$ 74.4

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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