Other Balance Sheet Items (Property and Equipment, Net) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Capitalized Computer Software, Net	$ 411.7	$ 402.7
Buildings and Improvements, Gross	260.2	257.5
Land	37.9	31.1
Furniture and Fixtures, Gross	11.0	10.4
Construction in Progress, Gross	15.3	3.6
Leasehold Improvements, Gross	1.6	1.5
Total Cost	737.7	706.8
Less: accumulated depreciation	(499.5)	(474.8)
Total property and equipment, net	$ 238.2	$ 232.0

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 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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