Income taxes - Reconciliation of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands |
Dec. 31, 2017 |
Dec. 31, 2016 |
|---|---|---|
| Deferred tax liabilities | ||
| Property, plant and equipment | $ (2,159) | $ (1,880) |
| Accruals | (3) | (326) |
| Deferred tax liabilities | (2,162) | (2,206) |
| Deferred tax assets | ||
| Share-based compensation expense | 5,603 | 4,632 |
| Available-for-sale debt securities | 33 | |
| Other accruals | 602 | 574 |
| Net operating loss and expenditure credit carryforwards | 23,357 | 14,613 |
| Deferred tax assets | 29,595 | 19,819 |
| Valuation allowance | (27,433) | (17,613) |
| Deferred tax assets, net | $ 2,162 | $ 2,206 |
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards and deductible tax credit carryforwards. No definition available.
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- Definition It represents the amount of deferred tax assets, tax deferred expense, compensation and benefits, available-for-sale debt securities. No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences from reserves and accruals, classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from reserves and accruals. No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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