Income Taxes - Additional Information (Details) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Tax Credit Carryforward [Line Items] | ||
| Foreign income (loss) | $ 3,686 | $ 1,791 |
| Unrecognized tax benefits | 0 | 0 |
| Penalties and interest accrued related to uncertain tax positions | 0 | 0 |
| Non-capital tax losses | 96,495 | 17,728 |
| Research Tax Credit Carryforward | ||
| Tax Credit Carryforward [Line Items] | ||
| Tax credit carryforwards | 13,148 | 12,683 |
| Investment Tax Credit Carryforward | ||
| Tax Credit Carryforward [Line Items] | ||
| Tax credit carryforwards | 3,762 | $ 3,435 |
| Domestic Tax Authority | ||
| Tax Credit Carryforward [Line Items] | ||
| Non-capital tax losses | $ 80,458 | |