Segment Information and Geographic Information - Property and Equipment, Net By Geographic Area (Detail) - USD ($) $ in Thousands |
Dec. 31, 2015 |
Dec. 31, 2014 |
|---|---|---|
| Revenues from External Customers and Long-Lived Assets [Line Items] | ||
| Property and equipment, net | $ 7,532 | $ 7,922 |
| United States [Member] | ||
| Revenues from External Customers and Long-Lived Assets [Line Items] | ||
| Property and equipment, net | 6,633 | 7,603 |
| Other [Member] | ||
| Revenues from External Customers and Long-Lived Assets [Line Items] | ||
| Property and equipment, net | $ 899 | $ 319 |