Fair Value Measurements (Detail) - USD ($) |
1 Months Ended | 3 Months Ended | 6 Months Ended | ||||
---|---|---|---|---|---|---|---|
Jan. 29, 2015 |
Jan. 31, 2015 |
Jun. 30, 2016 |
Jun. 30, 2015 |
Jun. 30, 2016 |
Jun. 30, 2015 |
Oct. 31, 2012 |
|
Fair Value Disclosures [Abstract] | |||||||
Debt instrument, face amount | $ 5,400,000.0 | ||||||
Number of convertible note payable converted in to common stock (in shares) | 1,356,738 | ||||||
Conversion price per share (in dollars per share) | $ 4.00 | ||||||
Stock price at date of conversion (in dollars per share) | $ 18.58 | ||||||
Gain (loss) in estimated fair value of convertible note payable | $ (1,800,000) | $ 0 | $ 0 | $ 0 | $ (1,811,000) |