PROPERTY, PLANT AND EQUIPMENT - Schedule of Property, Plant, and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 50.4	$ 58.2
Less accumulated depreciation and amortization	33.8	40.4
Property, plant and equipment, net	16.6	17.8
Depreciation	3.9	3.9	$ 3.5
Disposals of property plant and equipment	10.5
Accumulated depreciation	10.5
Land improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	0.8	0.8
Furniture and fixtures, office, computer and other equipment and software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	36.5	44.3
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 13.1	$ 13.1

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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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount of divestiture of long-lived, 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, furniture and fixtures, and computer equipment.

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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 of accumulated depreciation of long-lived, physical assets used to produce goods and services and not intended for resale, classified as other.

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