Stockholders' Equity and Redeemable Convertible Preferred Stock (Details 2) - Stock Option [Member]	3 Months Ended
Mar. 31, 2017 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	310,091
Employee options granted \| shares
Outstanding at ending \| shares	310,091
Options vested and expected to vest \| shares	310,091
Options vested and exercisable \| shares	310,091
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding at beginning \| $ / shares	$ 82.25
Employee options granted \| $ / shares
Outstanding at ending \| $ / shares	82.25
Options vested and expected to vest \| $ / shares	82.25
Options vested and exercisable \| $ / shares	$ 82.25
Share-based Compensation Arrangement by Share-based Payment Award, Options, Total Intrinsic Value [Roll Forward]
Outstanding at beginning \| $
Employee options granted \| $
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	4 years 1 month 6 days
Outstanding at ending	3 years 10 months 24 days
Options vested and expected to vest	3 years 10 months 24 days
Options vested and exercisable	3 years 9 months 18 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
Employee options granted \| shares
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
Employee options granted \| $ / shares
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 \| $
Employee options granted \| $
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	4 years 4 months 24 days
Outstanding at ending	4 years 2 months 12 days
Options vested and expected to vest	4 years 2 months 12 days
Options vested and exercisable	4 years 2 months 12 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 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

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The number of exercisable share options (fully vested and expected to vest) that may be converted as of the balance sheet date.

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As of the balance sheet date, the weighted-average exercise price (at which grantees can acquire the shares reserved for issuance) for exercisable stock options that are fully vested or expected to vest.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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

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