Fixed Assets, Net (Fixed Assets Stated at Cost) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Fixed assets	$ 19,231	$ 18,907
Less: accumulated depreciation	(14,385)	(13,705)
Fixed assets, net	4,846	5,202
Office Equipment [Member]
Fixed assets	$ 4,349	4,386
Property, Plant and Equipment, Useful Life	3 years
Leasehold Improvements [Member]
Fixed assets	$ 10,743	10,489
Property, Plant and Equipment, Estimated Useful Lives	Shorter of remaining lease term or useful life
Furniture and Fixtures [Member]
Fixed assets	$ 4,139	$ 4,032
Property, Plant and Equipment, Useful Life	7 years

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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Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and 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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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