Income Tax - Effective Income Tax Reconciliation (Details)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
U.S. Federal statutory rate	34.00%	34.00%
State rate, net of federal benefit	7.80%	1.30%
Permanent differences:
Change in tax rate	(113.00%)	0.00%
Deferred tax adjustment	(19.10%)	0.00%
Stock based compensation	28.90%	(1.10%)
Foreign tax rate difference	19.30%	(0.40%)
Other	3.00%	0.00%
Change in valuation allowance	40.00%	(33.90%)
Income tax provision	0.90%	(0.10%)

Effective Income Tax Rate Reconciliation, Deferred Tax Adjustment

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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 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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