Sale of Common Stock and Initial Public Offering - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands |
6 Months Ended | |||||
|---|---|---|---|---|---|---|
Mar. 27, 2015 |
Mar. 18, 2015 |
Jun. 30, 2015 |
Feb. 28, 2015 |
Feb. 27, 2015 |
Dec. 31, 2014 |
|
| Class of Stock [Line Items] | ||||||
| Net proceeds from sale of common stock | $ 33,767 | |||||
| Common stock, shares authorized | 30,000,000 | 30,000,000 | 12,500,000 | 12,500,000 | ||
| IPO [Member] | ||||||
| Class of Stock [Line Items] | ||||||
| Number of shares sold | 1,642,000 | 1,897,000 | ||||
| Net proceeds from sale of common stock | $ 33,800 | |||||
| Common stock per share | $ 19.50 | |||||
| Stock options exercised | 255,000 |