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Stockholders' Equity - Additional Information (Detail) - USD ($) |  |  | 6 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Apr. 29, 2015 | Nov. 13, 2014 | Sep. 30, 2014 | Sep. 30, 2015 | Mar. 31, 2015 | Nov. 15, 2013
Stockholders Equity [Line Items] |  |  |  |  |  |
Common stock |  |  |  | $ 141,000 | $ 96,000 |
Proceeds From Issuance Of Common Stock | $ 22,300,000 | $ 9,100,000 |  |  |  |
Sale of stock, price per share |  | $ 11.00 |  |  |  |
Common stock units offered |  | 909,090 |  |  |  |
Warrants to purchase one share of common stock |  | 90.00% |  |  |  |
Number of warrants issued to purchase common stock |  | 818,181 |  |  |  |
MLV, & Co. LLC | At Market Sales Agreement |  |  |  |  |  |
Stockholders Equity [Line Items] |  |  |  |  |  |
Commission on sale of common stock under the ATM |  |  |  |  |  | 3.00%
Proceeds From Issuance Of Common Stock |  |  | $ 4,900,000 |  |  |
Common stock, shares issued |  |  | 290,741 |  |  |
Sale of stock, price per share |  |  | $ 17.16 |  |  |
Cowen and Company, LLC |  |  |  |  |  |
Stockholders Equity [Line Items] |  |  |  |  |  |
Proceeds From Issuance Of Common Stock | $ 22,300,000 |  |  |  |  |
Common stock, shares issued | 4,000,000 |  |  |  |  |
Sale of stock, price per share | $ 6.00 |  |  |  |  |
Maximum | MLV, & Co. LLC | At Market Sales Agreement |  |  |  |  |  |
Stockholders Equity [Line Items] |  |  |  |  |  |
Common stock |  |  |  |  |  | $ 30,000,000

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- Definition 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. + 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 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5 + Details
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