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Income Tax - Reconciliation of Income Tax Attributable to Operations (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Income Tax Disclosure [Abstract] |  |  |
Income tax recovery at statutory rates (at a rate of 21% for all years presented) | $ (8,894) | $ (6,962) | $ (3,094)
Expenses not deducted for tax purposes | 299 | 224 | 118
Effect of tax rate changes on deferred tax assets and liabilities | (18) | 17 | 34
Rate differential on foreign earnings | (26) | (77) | (103)
Research and development tax credits | (1,154) | (134) | (23)
Change in valuation allowance | 10,464 | 7,544 | 3,662
Reassessment of previously recognized net operating losses | 9 | (620) |
Adjustment to prior year research and development tax credits | (731) |  |
Other | $ 51 | $ 8 | $ (594)

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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319 + Details
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 15 -URI https://asc.fasb.org/extlink&oid=123427490&loc=d3e32059-109318 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319 + Details
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- Definition The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319 + Details
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