Supplementary Data Property and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Furniture and equipment	$ 581.9	$ 632.8
Leasehold improvements	501.8	507.0
Internal-use computer software	603.2	585.1
Land and buildings	138.0	136.7
Total property and equipment, gross	1,824.9	1,861.6
Less: accumulated depreciation and amortization	(1,258.1)	(1,224.9)
Total property and equipment, net	566.8	636.7
Depreciation	$ 177.1	$ 180.3	$ 189.3

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.

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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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