Fixed Assets - Summary of Fixed Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Property Plant And Equipment Useful Life And Values [Abstract]
Office equipment	$ 34.2	$ 32.9
Furniture and fixtures	151.8	154.1
Leasehold improvements	259.9	232.6
Computer equipment	362.6	353.5
Land and buildings - corporate headquarters	171.6	168.9
Software	720.7	722.9
Other	41.3	31.3
Work in process	64.2	54.1
Gross fixed assets	1,806.3	1,750.3
Accumulated depreciation	(1,156.0)	(1,023.9)
Net fixed assets	$ 650.3	$ 726.4

Computer Equipment, Gross

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Land and buildings gross.

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- Definition

Property Plant and Equipment Useful Life and Values [Abstract]

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No definition available.

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

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.

+ References

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

+ References

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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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