401(k) Plan - Additional Information (Detail) (USD $)
In Thousands, unless otherwise specified |
12 Months Ended | ||
---|---|---|---|
Dec. 31, 2014
|
Dec. 31, 2013
|
Dec. 31, 2012
|
|
Compensation and Retirement Disclosure [Abstract] | |||
Defined contribution plan, matching percentage | 4.00% | ||
Defined contribution plan, matching amount | $ 197 | $ 91 | $ 49 |