Capitalization and Equity Structure - Additional Information (Details) |
12 Months Ended | ||
|---|---|---|---|
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Aug. 21, 2018
USD ($)
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Dec. 31, 2018
USD ($)
$ / shares
shares
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Dec. 31, 2017
shares
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| Class of Warrant or Right [Line Items] | |||
| Common Stock, shares authorized (in shares) | 141,429,000 | 141,429,000 | |
| Convertible Preferred stock, shares authorized (in shares) | 10,000,000 | 10,000,000 | |
| Common Stock, shares outstanding (in shares) | 62,963,000 | 59,943,000 | |
| Convertible Preferred stock, shares issued (in shares) | 0 | 0 | |
| Reverse stock split conversion | 0.1429 | ||
| Aggregate proceeds | $ | $ 4,446,000 | ||
| Common Stock | At-The-Market Offering | |||
| Class of Warrant or Right [Line Items] | |||
| Value of aggregate offering | $ | $ 25,000,000 | ||
| Number of shares sold (in shares) | 2,032,000 | ||
| Sale of shares (in dollars per share) | $ / shares | $ 2.39 | ||
| Stock available for issuance | $ | $ 20,134,000 |
| X | ||||||||||
- Definition Proceeds from issuance of common stock and from issuance of rights to purchase common shares at a predetermined price. No definition available.
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- Definition Sale Of Stock, Stock Available For Issuance, Value No definition available.
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- Definition Sale Of Stock, Value Of Aggregate Offering No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition The maximum number of common shares permitted to be issued by an entity's charter and bylaws. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The number of shares issued or sold by the subsidiary or equity method investee per stock transaction. No definition available.
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- Definition Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction. No definition available.
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- Definition Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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- Details
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