Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	100,000,000us-gaap_CommonStockSharesAuthorized	12,000,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	15,225,980us-gaap_CommonStockSharesIssued	4,404,407us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	15,225,980us-gaap_CommonStockSharesOutstanding	4,404,407us-gaap_CommonStockSharesOutstanding
Preferred stock, shares authorized	8,000,000us-gaap_PreferredStockSharesAuthorized
Series C-1 Convertible Preferred Stock [Member]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	11,000	11,000
Preferred stock, shares issued	3,917	7,016
Preferred stock, shares outstanding	3,917	7,016
Preferred stock, liquidation preference	$ 3,917	$ 7,016
Series F Convertible Preferred Stock [Member]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000	10,000
Preferred stock, shares issued	2,798	3,250
Preferred stock, shares outstanding	2,798	3,250
Preferred stock, liquidation preference	$ 2,798	$ 3,250

Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Value of the difference between preference in liquidation and the par or stated values of the preferred shares.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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