Other Balance Sheet Items (Property And Equipment, Net) (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Computer equipment and software	$ 418.7	$ 409.0
Buildings and building improvements	264.8	261.3
Land	37.9	37.9
Office equipment and furniture	11.1	11.0
Capital work in progress	16.9	16.1
Leasehold improvements	1.6	1.6
Total cost	751.0	736.9
Less: accumulated depreciation and amortization	(526.5)	(503.7)
Total property and equipment, net	$ 224.5	$ 233.2

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 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.

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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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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 additions or improvements to assets held under a lease arrangement.

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