Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal statutory rate	(35.00%)	(35.00%)
Adjustments for tax effects of:
State taxes, net	(7.40%)	(1.70%)
Stock-based compensation	16.10%	2.30%
Foreign taxes	1.20%	0.10%
Tax law change	459.10%
Fair market value adjustments	(92.10%)	0.40%
Other permanent adjustments	1.30%	0.30%
Tax rate adjustment	(19.10%)	0.30%
Uncertain tax positions	(4.90%)	(0.10%)
Other	21.80%	0.90%
Valuation allowance	(341.80%)	17.50%
Effective income tax rate	(0.80%)	(15.00%)

Effective income tax rate reconciliation adjustments for tax effects.

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Effective Income Tax Rate Reconciliation, Fair Market Value Adjustments

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Effective Income Tax Rate Reconciliation Permanent Differences

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Effective income tax rate reconciliation tax law change.

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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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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 income tax contingencies. Includes, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

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