Balance Sheet Components (Schedule of Property and Equipment, Net) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Total property and equipment, gross	$ 122,739	$ 116,108
Accumulated depreciation and amortization	(101,665)	(95,931)
Total property and equipment, net	21,074	20,177
Computer equipment
Total property and equipment, gross	9,815	9,205
Furniture, fixtures and leasehold improvements
Total property and equipment, gross	18,447	18,286
Software
Total property and equipment, gross	28,299	28,065
Machinery and equipment
Total property and equipment, gross	$ 66,178	$ 60,552

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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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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