Stock-based Compensation - Additional Information (Detail) - USD ($) |
3 Months Ended | 6 Months Ended | ||||
|---|---|---|---|---|---|---|
Jun. 30, 2015 |
Mar. 31, 2015 |
Dec. 31, 2014 |
Jun. 30, 2014 |
Jun. 30, 2015 |
Jun. 30, 2014 |
|
| Stock Based Compensation [Line Items] | ||||||
| Number of shares, Options outstanding | 2,616,735 | 2,544,500 | 2,519,500 | 2,616,735 | ||
| Number of shares, Options granted | 72,235 | 25,000 | ||||
| Share-based payment award, award vesting period | 3 years | |||||
| Maximum term of stock options | 10 years | |||||
| Weighted average grant date fair value | $ 130,456 | $ 176,898 | ||||
| Number of shares, Options exercised | 0 | 0 | 0 | 0 | 0 | |
| Options vested | 200,673 | 375,319 | ||||
| Unrecognized share-based compensation expense | $ 2,253,478 | $ 2,253,478 | ||||
| Recognized weighted average service period | 2 years 6 months | |||||
| Pieris Plan [Member] | ||||||
| Stock Based Compensation [Line Items] | ||||||
| Common stock reserved for issuance | 3,200,000 | |||||
| Share-based compensation description | (i) 1,000,000 shares, (ii) 4% of the number of shares of the Company's common stock outstanding on such date, and (iii) such other amount determined by the Compensation committee of the Board of Directors. As of June 30, 2015, options to purchase 1,470,235 shares of the Company's common stock are outstanding under the Pieris Plan to its executive officers and directors. 40,235 of these shares were granted during the second quarter of 2015. All other shares were granted in the fourth quarter of 2014. | |||||
| Common stock available for grant | 583,265 | 583,265 | ||||
| Pieris Plan [Member] | Executive Officers And Directors [Member] | ||||||
| Stock Based Compensation [Line Items] | ||||||
| Number of shares, Options outstanding | 1,470,235 | 1,470,235 | ||||
| Number of shares, Options granted | 40,235 | |||||
| Pieris Plan [Member] | Other Employees and Consultants [Member] | ||||||
| Stock Based Compensation [Line Items] | ||||||
| Number of shares, Options outstanding | 1,146,500 | 1,146,500 | ||||
| Number of shares, Options granted | 32,000 | 25,000 | 1,089,500 | |||