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Convertible Preferred Stock Liability (Details) $ / shares in Units, $ in Thousands |  |  | 1 Months Ended | 3 Months Ended | 6 Months Ended | 11 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 10, 2015 | Nov. 26, 2014 USD ($) item shares | Jun. 30, 2015 USD ($) $ / shares shares | Jan. 31, 2015 USD ($) shares | Mar. 31, 2015 | Jun. 30, 2015 USD ($) | Dec. 31, 2014 USD ($) shares | Dec. 31, 2015 USD ($) shares | Dec. 31, 2014 shares | Dec. 31, 2016 shares
Convertible preferred stock |  |  |  |  |  |  |  |  |  |
Shares Authorized | shares |  |  |  |  |  |  | 8,921,438 | 14,274,741 | 8,921,438 | 0
Net proceeds |  |  |  |  |  |  | $ 12,611 | $ 95,569 |  |
Change in fair value of convertible preferred stock liability |  |  |  |  |  |  |  | $ 17,600 |  |
Series A convertible preferred stock |  |  |  |  |  |  |  |  |  |
Convertible preferred stock |  |  |  |  |  |  |  |  |  |
Shares Authorized | shares |  | 8,921,438 |  |  |  |  |  | 8,921,429 |  |
Issuance of stock (in shares) | shares |  | 3,395,468 | 4,460,715 | 1,065,246 |  |  | 3,395,468 | 5,525,961 |  |
Net proceeds |  | $ 12,600 | $ 16,700 | $ 4,000 |  |  |  |  |  |
Number of defined triggers for issuance of additional shares to first tranche investors on the same terms | item |  | 3 |  |  |  |  |  |  |  |
Convertible preferred stock liability |  | $ 2,600 |  |  |  |  |  |  |  |
Change in fair value of convertible preferred stock liability |  |  |  |  |  | $ 17,600 |  |  |  |
Reclassification of liability to convertible preferred stock |  |  | $ 20,200 |  |  |  |  |  |  |
Series A convertible preferred stock | Obligation to issue second tranche |  |  |  |  |  |  |  |  |  |
Convertible preferred stock |  |  |  |  |  |  |  |  |  |
Fixed price for second tranche obligation (in dollars per share) | $ / shares |  |  | $ 3.755 |  |  |  |  |  |  |
Assumed term | 2 years |  |  |  | 9 months |  |  |  | 1 year |
Interest rate (as a percent) | 0.75% |  |  |  | 0.20% |  |  |  | 0.13% |
Volatility (as a percent) | 75.00% |  |  |  | 85.00% |  |  |  | 85.00% |

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- Definition The amount recognized in earnings for the change in fair value of the obligation to issue convertible preferred stock at fixed terms. + References No definition available. + Details
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- Definition The number of defined triggers, upon the earliest of which the investors of the first tranche of the convertible preferred stock agreed to purchase a pro-rata portion of shares in the second tranche and the entity agreed to sell such shares on the same terms as the first tranche. + References No definition available. + Details
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- Definition Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition The maximum number of securities classified as temporary equity that are permitted to be issued by an entity's charter and bylaws. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(27)(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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