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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Financial Statements Details - Property and Equipment, Net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	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	$ 159,794		$ 159,794		$ 143,299
Less: accumulated depreciation	(84,397)		(84,397)		(69,020)
Property and equipment, net	75,397		75,397		74,279
Depreciation	5,400	$ 5,200	16,000	$ 15,000
Equipment and machinery
Property, Plant and Equipment [Line Items]
Property and equipment, gross	54,169		54,169		47,711
Computer hardware and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	28,549		28,549		22,124
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,641		3,641		3,020
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	36,350		36,350		30,548
Building
Property, Plant and Equipment [Line Items]
Property and equipment, gross	35,154		35,154		35,154
Construction-in-process
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,931		$ 1,931		$ 4,742