Stockholders' Equity and Redeemable Convertible Preferred Stock (Details 1) - Stock Option [Member] $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($) $ / shares shares
Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number of Shares [Roll Forward]
Outstanding at beginning \| shares	325,597
Employee options granted \| shares	200,000
Outstanding at ending \| shares	525,597
Options vested and expected to vest \| shares	525,597
Options vested and exercisable \| shares	500,597
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding at beginning \| $ / shares	$ 78.20
Employee options granted \| $ / shares	1.39
Outstanding at ending \| $ / shares	48.97
Options vested and expected to vest \| $ / shares	48.97
Options vested and exercisable \| $ / shares	$ 51.36
Share-based Compensation Arrangement by Share-based Payment Award, Options, Total Intrinsic Value [Roll Forward]
Outstanding at beginning \| $	$ 5,999
Employee options granted \| $
Employee options expired \| $
Outstanding at ending \| $
Options vested and expected to vest \| $
Options vested and exercisable \| $
Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Remaining Contractual Life [Roll Forward]
Outstanding at beginning	3 years 2 months 12 days
Employee options granted	9 years 4 months 24 days
Outstanding at ending	5 years 1 month 6 days
Options vested and expected to vest	5 years 1 month 6 days
Options vested and exercisable	4 years 10 months 24 days
Non-Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number of Shares [Roll Forward]
Outstanding at beginning \| shares	2,893
Outstanding at ending \| shares	2,893
Options vested and expected to vest \| shares	2,893
Options vested and exercisable \| shares	2,893
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding at beginning \| $ / shares	$ 98.07
Outstanding at ending \| $ / shares	98.07
Options vested and expected to vest \| $ / shares	98.07
Options vested and exercisable \| $ / shares	$ 98.07
Share-based Compensation Arrangement by Share-based Payment Award, Options, Total Intrinsic Value [Roll Forward]
Outstanding at beginning \| $
Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Remaining Contractual Life [Roll Forward]
Outstanding at beginning	3 years 4 months 24 days
Outstanding at ending	2 years 8 months 4 days
Options vested and expected to vest	2 years 8 months 4 days
Options vested and exercisable	2 years 8 months 4 days

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The expired-date intrinsic value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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The grant-date intrinsic value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Gross 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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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. 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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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 exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. 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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Number of fully vested and expected to vest options outstanding that can 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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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. 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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