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Income Tax - Summary of Investment Tax Credits and Non-Capital Losses and Net Operating Losses (Detail) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | $ 34,800 | $ 25,300
Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | 105,596 |
UK |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 3,236 | 2,700
US [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 34,797 |
Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 3,029 |
Investment tax credits carryforwards [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 2,800 | $ 2,900
2020 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 2 |
2021 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 2 |
2022 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 1 |
2025 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 244 |
2026 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | 7,660 |
2026 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 71 |
2027 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | 6,082 |
2028 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | 7,256 |
2028 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 111 |
2029 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | 1,712 |
2029 [Member] | US [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 9 |
2029 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 237 |
2030 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | 6,770 |
2030 [Member] | US [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 5 |
2030 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 346 |
2031 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | 12,354 |
2031 [Member] | US [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 17 |
2031 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 486 |
2032 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | 17,278 |
2032 [Member] | UK |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 42 |
2032 [Member] | US [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 43 |
2032 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 363 |
2033 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | 23,240 |
2033 [Member] | UK |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 54 |
2033 [Member] | US [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 2 |
2033 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 193 |
2034 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | 17,077 |
2034 [Member] | UK |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 46 |
2034 [Member] | US [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 3 |
2034 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 215 |
2035 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | 3,112 |
2035 [Member] | UK |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 27 |
2035 [Member] | US [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 654 |
2035 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 122 |
2036 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | 5,361 |
2036 [Member] | UK |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 58 |
2036 [Member] | US [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 611 |
2036 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 80 |
2037 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | (5,295) |
2037 [Member] | UK |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 654 |
2037 [Member] | US [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 8,763 |
2037 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 22 |
2038 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | (3,179) |
2038 [Member] | UK |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 955 |
2038 [Member] | US [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 7,207 |
2038 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 202 |
2039 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | 4,443 |
2039 [Member] | UK |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 869 |
2039 [Member] | US [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 7,982 |
2039 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | 220 |
2040 [Member] | Canada |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Non-capital Losses | 1,725 |
2040 [Member] | UK |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 531 |
2040 [Member] | US [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Net Operating Losses | 9,501 |
2040 [Member] | Investment tax credits carryforwards [Member] |  |
Schedule Of Tax Credits And Losses Carry Forward Expiration [Line Items] |  |
Investment Tax Credits | $ 112 |

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