Fair Value of Outstanding Derivative Instruments (Detail) - USD ($) $ in Thousands |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Derivative [Line Items] | ||
| Derivative assets | $ 6 | $ 9 |
| Foreign exchange forward contracts | Derivatives designated as cash flow hedging instruments | ||
| Derivative [Line Items] | ||
| Derivative assets | $ 6 | $ 9 |