Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Building and leasehold improvements	$ 123.0	$ 120.4
Computer and data processing equipment	116.4	101.7
Machinery and equipment	45.6	43.2
Land	27.7	27.7
Furnitures and fixtures	22.7	23.8
Construction in progress	17.9	20.4
Computer software	9.6	10.8
Property and equipment, gross	362.9	348.0
Less: accumulated depreciation	(201.8)	(184.3)
Property and equipment, net	$ 161.1	$ 163.7

Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

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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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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Amount before accumulated depreciation, depletion and amortization of other physical assets used in the normal conduct of business to produce goods and services and not intended for resale.

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The cumulative amount of depreciation (related to long-lived, depreciable flight assets owned by the entity and used in the entity's principle business operations and capitalized assets classified as property, plant and equipment that are owned by the entity) that has been recognized in the income statement.

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