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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- Definition

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 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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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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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Property, Plant, and Equipment (Details) - USD ($)	3 Months Ended		9 Months Ended
Property, Plant, and Equipment (Details) - USD ($)	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 87,077,000		$ 87,077,000		$ 92,540,000
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(60,337,000)		(60,337,000)		(63,890,000)
Property, Plant and Equipment, Net	26,740,000		26,740,000		28,650,000
Depreciation	2,100,000	$ 2,400,000	6,200,000	$ 7,300,000
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	42,999,000		42,999,000		47,269,000
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	17,602,000		17,602,000		17,740,000
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 26,476,000		$ 26,476,000		$ 27,531,000