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Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024
Income Tax [Line Items] |  |
Federal statutory rate | 21.00% | 21.00%
Deferred tax assets increase decrease in the valuation allowance | $ 55,896 |
Percentage of future taxable income against which net operating loss with no definite period shall be set off | 80.00% |
Unrecognized tax benefits accrued interest and penalties | $ 192 | $ 173
United Kingdom |  |
Income Tax [Line Items] |  |
Net operating loss carry forwards | 273,143 |
Domestic Country [Member] |  |
Income Tax [Line Items] |  |
Net operating loss carry forwards | 273,444 |
Net operating loss carryforwards subject to annual limitation | $ 75,361 |
Percentage of future taxable income against which net operating loss with definite period shall be set off | 100.00% |
Domestic Country [Member] | 2028 to 2037 [Member] |  |
Income Tax [Line Items] |  |
Net operating loss carry forwards | $ 103,081 |
Domestic Country [Member] | Indefinitely [Member] |  |
Income Tax [Line Items] |  |
Net operating loss carry forwards | 170,363 |
Domestic Country [Member] | 2035 to 2045 [Member] |  |
Income Tax [Line Items] |  |
Tax credit carryforward | 8,643 |
Tax credit carryforwards subject to annual limitation | 1,774 |
State and Local Jurisdiction [Member] |  |
Income Tax [Line Items] |  |
Tax credit carryforward | 3,095 |
State and Local Jurisdiction [Member] | Indefinitely [Member] |  |
Income Tax [Line Items] |  |
Tax credit carryforward | 2,901 |
State and Local Jurisdiction [Member] | 2027 through 2045 [Member] |  |
Income Tax [Line Items] |  |
Net operating loss carry forwards | 24,368 |
State and Local Jurisdiction [Member] | 2029 to 2040 [Member] |  |
Income Tax [Line Items] |  |
Tax credit carryforward | $ 194 |

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