Balance Sheet Components (Property) (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2015	Dec. 31, 2014
Property and Equipment, net
Property and equipment, gross	$ 27,579	$ 24,168
Less: Accumulated depreciation and amortization	(12,532)	(9,594)
Total Property and Equipment, net	15,047	14,574
Machinery and equipment
Property and Equipment, net
Property and equipment, gross	23,136	18,632
Machinery and equipment \| Equipment Financing Facility
Property and Equipment, net
Equipment pledged	4,700
Furniture and fixtures
Property and Equipment, net
Property and equipment, gross	$ 217	217
Useful Life	3 years
Software
Property and Equipment, net
Property and equipment, gross	$ 1,508	700
Useful Life	3 years
Leasehold improvements
Property and Equipment, net
Property and equipment, gross	$ 1,674	1,036
Construction-in-process
Property and Equipment, net
Property and equipment, gross	$ 1,044	$ 3,583
Minimum \| Machinery and equipment
Property and Equipment, net
Useful Life	3 years
Maximum \| Machinery and equipment
Property and Equipment, net
Useful Life	5 years

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 of assets pledged to secure a debt instrument.

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+ References

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+ References

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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.

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