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 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 and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 9,435		$ 9,435		$ 9,322
Accumulated Depreciation and Amortization	(3,804)		(3,804)		(3,063)
Total	5,631		5,631		6,259
Depreciation expense	245	$ 256	746	$ 757
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	6,832		6,832		6,832
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,191		1,191		1,190
Computer Hardware
Property Plant And Equipment [Line Items]
Property and equipment, gross	768		768		686
Computer Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	370		370		333
Office Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 274		$ 274		$ 281