Components of Accrued Liabilities (Detail) - USD ($) $ in Thousands |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|---|---|---|---|
| Components of accrued liabilities | |||
| Payroll and benefits | $ 2,147 | $ 2,303 | |
| Warranty accrual, current portion | 933 | 1,345 | $ 930 |
| Taxes | 638 | 445 | |
| Accrued professional services | 782 | 681 | |
| Accrued capital lease, current portion | 159 | 167 | |
| Accrued insurance premium | 906 | 467 | |
| Other | 213 | 498 | |
| Accrued liabilities | $ 5,778 | $ 5,906 |