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 expense recognized in the current period that allocates the cost of nonproduction tangible assets over their useful lives.

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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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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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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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Property and Equipment - Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 17,670	$ 15,231
Less accumulated depreciation	(13,280)	(12,326)
Property and equipment, net	4,390	2,905
Depreciation expense	$ 1,200	900	$ 900
Leasehold Improvements
Property Plant And Equipment [Line Items]
Depreciable life	Shorter of estimated useful life or life of lease
Property and equipment, gross	$ 3,278	3,227
Office furniture, fixtures and equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 14,392	$ 12,004
Office furniture, fixtures and equipment \| Minimum
Property Plant And Equipment [Line Items]
Depreciable life	2 years
Office furniture, fixtures and equipment \| Maximum
Property Plant And Equipment [Line Items]
Depreciable life	10 years