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Stockholders' Equity (Deficit) - Additional Information (Detail) (USD $) | 9 Months Ended | 12 Months Ended |  |  | 24 Months Ended |  | 9 Months Ended | 1 Months Ended | 9 Months Ended | 1 Months Ended | 9 Months Ended | 1 Months Ended | 9 Months Ended
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Sep. 30, 2013 | Dec. 31, 2011 | May 31, 2006 | Oct. 31, 2004 | Dec. 31, 2003 Series A Preferred Stock [Member] | Sep. 30, 2013 Series A Preferred Stock [Member] | Sep. 30, 2013 Series D Preferred Stock [Member] | Mar. 31, 2011 Series D Preferred Stock [Member] Raven Biotechnologies Inc [Member] | Jul. 31, 2008 Series D Preferred Stock [Member] Raven Biotechnologies Inc [Member] | Jan. 31, 2011 Series D Two Preferred Stock [Member] | May 30, 2010 Series D Two Preferred Stock [Member] | Sep. 30, 2008 Series D Two Preferred Stock [Member] | Sep. 30, 2013 Series D Two Preferred Stock [Member] | Sep. 30, 2013 Series A- One Preferred Stock [Member] | Sep. 30, 2013 Series A- Two Preferred Stock [Member] | Oct. 31, 2004 Series B Preferred Stock [Member] | Sep. 30, 2013 Series B Preferred Stock [Member] | May 31, 2006 Series C Preferred Stock [Member] | Sep. 30, 2013 Series C Preferred Stock [Member]
Stockholders Equity [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued or sold |  |  |  |  | 34,239,374 |  |  |  |  | 18,427,388 | 6,916,110 | 38,337,678 |  |  |  | 71,401,237 |  | 110,952,217 |
Proceeds from issuance of convertible preferred stock |  | $ 12,014,816 |  |  | $ 34,000,000 |  |  |  |  | $ 12,016,500 |  | $ 24,843,211 |  |  |  | $ 30,261,672 |  | $ 44,898,754 |
Convertible Preferred Stock Per Share |  |  |  |  | $ 1.00 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related offering costs |  |  |  |  |  |  |  |  |  |  |  | 156,788 |  |  |  | 238,000 |  | 101,246 |
Shares of common stock allocated but unissued |  |  | 10,003,300 | 13,604,016 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued to acquire entity |  |  |  |  |  |  |  | 14,446,227 | 12,466,039 |  |  |  |  |  |  |  |  |  |
Purchased shares |  |  |  |  |  |  |  |  |  |  | 518,708 | 2,875,327 |  |  |  |  |  |  |
Exercise price |  |  |  |  |  |  |  |  |  |  |  |  | 0.65 |  |  |  |  |  |
Outstanding stock | 4,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of preferred stock holders with voting rights of board members | 66.67% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accrued noncumulative dividends on preferred stock |  |  |  |  |  |  | $ 0.0522 |  |  |  |  |  | $ 0.0522 | $ 0.08 | $ 0.08 |  | $ 0.0341 |  | $ 0.0324
Convertible preferred stock series |  |  |  |  |  |  | 1.00 |  |  |  |  |  | 1.00 | 1.506 | 1.00 |  | 1.14 |  | 1.00
Conversion price of preferred stock |  |  |  |  |  |  | $ 12.20 |  |  |  |  |  | $ 12.20 | $ 12.39 | $ 18.77 |  | $ 6.95 |  | $ 7.70
Reserved common stock | 17,129,782 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds from underwritten public offering upon closing of firm | $ 40,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Earning per share received by the shareholders |  |  |  |  |  | $ 12.39 | $ 12.20 |  |  |  |  |  | $ 12.20 |  |  |  | $ 6.95 |  | $ 7.70
Reverse stock split | 1-for-18.7739 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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