PROPERTY, EQUIPMENT AND SOFTWARE (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,193.2	$ 1,970.3
Less accumulated depreciation and amortization	1,457.0	1,274.9
Total	736.2	695.4
Computer and communications software and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,293.5	1,113.1
Buildings and improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	472.0	457.5
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	196.4	169.2
Furniture and other equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	205.6	193.3
Land
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 25.7	$ 37.2

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 before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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