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Fixed Assets (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Fixed assets, at cost	$ 213.3	$ 229.9
Accumulated depreciation and amortization	(146.0)	(161.4)
Fixed assets (net)	67.3	68.5
Buildings and leasehold improvements
Property, Plant and Equipment [Line Items]
Fixed assets, at cost	108.6	111.9
Software
Property, Plant and Equipment [Line Items]
Fixed assets, at cost	45.7	51.7
Office equipment
Property, Plant and Equipment [Line Items]
Fixed assets, at cost	20.7	25.6
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Fixed assets, at cost	17.5	19.9
Land, improvements and other
Property, Plant and Equipment [Line Items]
Fixed assets, at cost	$ 20.8	$ 20.8

X

- Definition

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, 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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