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Warrants and Derivative Liabilities - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands |  |  | 1 Months Ended | 3 Months Ended |
--- | --- | --- | --- | --- | ---
Dec. 19, 2014 | Apr. 04, 2012 | Oct. 31, 2013 | Jun. 30, 2017 | Jun. 30, 2016 | Nov. 13, 2014
Derivative [Line Items] |  |  |  |  |  |
Gain (loss) in change of fair value of derivative instruments and warrants (less than $0.1 million Hercules warrants) |  |  |  | $ 925 | $ (678) |
Hercules Warrants |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |
Gain (loss) in change of fair value of derivative instruments and warrants (less than $0.1 million Hercules warrants) |  |  |  | 100 | (100) |
November 2014 Warrant |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |
Gain (loss) in change of fair value of derivative instruments and warrants (less than $0.1 million Hercules warrants) |  |  |  | $ 900 | (600) |
Warrants expiration date |  |  |  | Nov. 13, 2019 |  |
Common stock units offered (in shares) |  |  |  |  |  | 909,090
Warrants to purchase one share of common stock |  |  |  |  |  | 0.9
Number of warrants issued to purchase common stock (in shares) |  |  |  |  |  | 818,181
Sale of stock, price per share (in dollars per share) |  |  |  |  |  | $ 7.98
Capital Ventures International | Exchanged Warrants |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |
Gain (loss) in change of fair value of derivative instruments and warrants (less than $0.1 million Hercules warrants) |  |  |  | $ 0 | $ 0 |
Senior convertible note warrant | Capital Ventures International | Original Warrants |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |
Number of shares received from warrants received to purchase common stock (in shares) |  | 309,406 |  |  |  |
Senior convertible note warrant | Capital Ventures International | Exchanged Warrants |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |
Warrant exercise, waiting period |  |  | 6 months |  |  |
Warrant exercise period |  |  | 5 years |  |  |
Warrant exercise price (in dollars per share) |  |  | $ 12.83 |  |  |
Senior convertible note warrant | Capital Ventures International | Maximum | Exchanged Warrants |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |
Beneficial ownership limitation percentage |  |  | 4.99% |  |  |
Beneficial ownership, limitation option, percentage |  |  | 9.99% |  |  |
Required notification period |  |  | 61 days |  |  |
Senior secured loan | Hercules Technology Growth Capital | Hercules Warrants |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |
Number of shares received from warrants received to purchase common stock (in shares) | 58,823 |  |  |  |  |
Warrant exercise price (in dollars per share) | $ 11.00 |  |  | $ 8.02 |  |
Warrants expiration date |  |  |  | Jun. 30, 2020 |  |

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