Stockholders' Equity (Deficit) (Details 2) - USD ($) shares in Thousands	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Options Shares
Outstanding, Beginning balance	736	71
Granted	393	502
Forfeited or expired	(73)	(7)
Outstanding, Ending balance	1,056	566
Vested and expected to vest	1,039	520
Exercisable	256	106
Weighted Average Exercise Price Per Share
Outstanding, Beginning balance	$ 3.65	$ 45.21
Granted	0.78	0.50
Forfeited or expired	14.86	7.21
Outstanding, Ending balance	1.81	6.02
Vested and expected to vest	1.78	6.04
Exercisable	$ 5.46	$ 29.05
Weighted Average Remaining Contractual Term (Years)
Outstanding	6 years 26 days	6 years 1 month 2 days
Vested and expected to vest	6 years 22 days	6 years 15 days
Exercisable	5 years 11 days	3 years 11 months 1 day
Aggregate Intrinsic Value
Outstanding, Beginning balance
Granted
Forfeited or expired
Outstanding, Ending balance
Vested and expected to vest
Exercisable

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Weighted average price of options that were either forfeited or expired.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Net number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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