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Income Tax - Additional Information (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Income Taxes [Line Items] |  |  |
Future enacted income tax rate assumed for both Federal and state deferred tax calculations | 21.00% | 21.00% | 21.00%
Deferred tax assets liabilities, valuation allowance | $ 55,500,000 |  |
Deferred tax assets | 0 |  |
Increase in allowance considered deferred tax assets | $ 7,500,000 |  |
Income tax rate assumed for both State and Foreign deferred tax calculations | 21.00% | 21.00% | 21.00%
Unrecognized tax benefits | $ 800,000 |  |
Accrued interest and penalties related to income taxes | $ 0 | $ 0 |
Canada [Member] |  |  |
Income Taxes [Line Items] |  |  |
Tax credit carryforwards expiration year | 2041 |  |
Non-capital loss carryforwards | $ 109,500 | 105,600 |
Unclaimed tax deductions related to scientific research and experimental development expenditures | 16,000 |  |
UK [Member] |  |  |
Income Taxes [Line Items] |  |  |
Operating loss carryforwards | 3,500 | 3,200 |
Research and Development Tax Credits [Member] |  |  |
Income Taxes [Line Items] |  |  |
Tax credit carryforwards | $ 400,000 | 300,000 |
Tax credit carryforwards expiration year | 2041 |  |
Research and Development Tax Credits [Member] | Canada [Member] |  |  |
Income Taxes [Line Items] |  |  |
Tax credit carryforwards | $ 2,700 | 2,800 |
Federal [Member] |  |  |
Income Taxes [Line Items] |  |  |
Operating loss carryforwards | $ 47,400,000 | $ 34,800,000 |
Operating loss carryforwards expiration year | 2021 |  |
Operating loss carryforwards indefinitely | $ 37,300,000 |  |

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