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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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 (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Property and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Property and equipment
Total property and equipment	$ 33,127		$ 33,127		$ 31,890
Accumulated depreciation	(19,478)		(19,478)		(17,451)
Property and equipment, net	13,649		13,649		14,439
Depreciation expense	1,000	$ 1,000	2,100	$ 1,900
Equipment
Property and equipment
Total property and equipment	18,824		$ 18,824		18,602
Equipment \| Minimum
Property and equipment
Estimated useful life			5 years
Equipment \| Maximum
Property and equipment
Estimated useful life			7 years
Furniture and fixtures
Property and equipment
Total property and equipment	954		$ 954		954
Furniture and fixtures \| Minimum
Property and equipment
Estimated useful life			5 years
Furniture and fixtures \| Maximum
Property and equipment
Estimated useful life			7 years
Computer and software
Property and equipment
Total property and equipment	8,919		$ 8,919		8,783
Estimated useful life			3 years
Leasehold improvements
Property and equipment
Total property and equipment	1,977		$ 1,977		1,978
Leasehold improvements \| Minimum
Property and equipment
Estimated useful life			2 years
Leasehold improvements \| Maximum
Property and equipment
Estimated useful life			8 years
Reusable instruments
Property and equipment
Total property and equipment	$ 2,453		$ 2,453		$ 1,573
Estimated useful life			5 years