Classification of Compensation Expense Associated with Share-Based Payments (Detail) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||
| Allocated Share-based Compensation Expense | $ 3,065 | $ 3,350 | $ 1,233 |
| Cost Of Revenue | |||
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||
| Allocated Share-based Compensation Expense | 226 | 333 | 134 |
| Sales and Marketing | |||
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||
| Allocated Share-based Compensation Expense | 477 | 679 | 401 |
| General and Administrative | |||
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||
| Allocated Share-based Compensation Expense | 2,051 | 2,020 | 616 |
| Engineering And Development | |||
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||
| Allocated Share-based Compensation Expense | $ 311 | $ 318 | $ 82 |