Income Taxes - Schedule of Reconciliation of the Federal Statutory Income Tax Rate to the Effective Tax Rate (Details)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Federal statutory rate	35.00%	35.00%	35.00%
Effect of:
State taxes, net of federal tax benefit	0.00%	0.60%	2.50%
Change in valuation allowance	(21.00%)	(11.20%)	13.40%
Research and development tax credit	1.10%	1.20%	0.80%
Convertible preferred stock warrants	0.00%	0.00%	(1.30%)
Stock-based compensation	(1.10%)	(1.90%)	2.90%
Foreign differential	(14.10%)	(15.60%)	(17.10%)
Non-deductible/non-taxable items	(0.60%)	(0.20%)	0.00%
Other, net	(0.10%)	(0.30%)	(3.20%)
Total	(0.80%)	7.60%	33.00%

Effective Income Tax Rate Reconciliation, Convertible Preferred Stock Warrants, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage of the difference, between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, that is attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority interest income (expense), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, change in enacted tax rate, prior year income taxes, change in deferred tax asset valuation allowance, and other adjustments.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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