Supplementary Data Property and Equipment (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Depreciation, Depletion and Amortization	$ 132.3	$ 130.6	$ 124.3
Furniture and equipment	640.7us-gaap_FurnitureAndFixturesGross	661.6us-gaap_FurnitureAndFixturesGross
Leasehold improvements	594.0us-gaap_LeaseholdImprovementsGross	611.4us-gaap_LeaseholdImprovementsGross
Internal use computer software	296.2	269.1
Land and buildings	87.3us-gaap_Land	109.6us-gaap_Land
Property and Equipment	1,618.2us-gaap_PropertyPlantAndEquipmentGross	1,651.7us-gaap_PropertyPlantAndEquipmentGross
Less: accumulated depreciation	1,070.0	1,111.7
Total property and equipment, net	$ 548.2us-gaap_PropertyPlantAndEquipmentNet	$ 540.0us-gaap_PropertyPlantAndEquipmentNet

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 amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

+ References

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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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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- Definition

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 additions or improvements to assets held under a lease arrangement.

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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.

+ References

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