Property, Equipment, and Software - Schedule of Property, Equipment and Software (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, equipment and software, gross	$ 204.4	$ 176.7
Less accumulated depreciation and amortization	(89.6)	(81.5)
Property, equipment and software, net	114.8	95.2
Buildings and land
Property, Plant and Equipment [Line Items]
Property, equipment and software, gross	4.6	4.6
Computer and other equipment
Property, Plant and Equipment [Line Items]
Property, equipment and software, gross	46.6	48.6
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, equipment and software, gross	30.9	27.9
Software
Property, Plant and Equipment [Line Items]
Property, equipment and software, gross	112.9	85.9
Office furniture
Property, Plant and Equipment [Line Items]
Property, equipment and software, gross	$ 9.4	$ 9.7

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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