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Income Tax - Narrative (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020
Schedule Of Income Tax [Line Items] |  |
Deferred tax asset | $ 54,400,000 | $ 31,489,000
Increase in valuation allowance | 22,517,000 |
Increase in net deferred tax assets due to change in enacted tax rate | 9,311,000 |
Increase in valuation allowance due to change in enacted tax rate | 9,311,000 |
Research and development tax relief | 15,206,000 | 9,363,000
Liability for unrecognized tax benefits | 0 | 0
Liability for interest and penalties | 0 | 0
Research and development tax credit carryforwards |  |
Schedule Of Income Tax [Line Items] |  |
Tax credit carryforward | 941,000 |
U.S. Federal |  |
Schedule Of Income Tax [Line Items] |  |
Operating loss carryforwards | 1,034,000 | $ 232,000
U.S. State |  |
Schedule Of Income Tax [Line Items] |  |
Operating loss carryforwards | 165,000 |
U.K. |  |
Schedule Of Income Tax [Line Items] |  |
Operating loss carryforwards | 191,714,000 |
Potential deferred tax asset | $ 47,929,000 |

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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319 + Details
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