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Leases - Summary of Maturity Analysis of Lease Liabilities (Detail) - GBP (£) £ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure Of Maturity Analysis Of Operating Lease Payments [Line Items] |  |  |
Total contractual undiscounted payments | £ 677 | £ 860 |
Less: effect of discounting | (32) | (54) |
Discounted lease liabilities | 645 | 806 | £ 434
Not later than 1 year [member] |  |  |
Disclosure Of Maturity Analysis Of Operating Lease Payments [Line Items] |  |  |
Total contractual undiscounted payments | 296 | 293 |
Later than 1 year and not later than 3 years [member] |  |  |
Disclosure Of Maturity Analysis Of Operating Lease Payments [Line Items] |  |  |
Total contractual undiscounted payments | 307 | 400 |
Later than 3 years and not later than 5 years [member] |  |  |
Disclosure Of Maturity Analysis Of Operating Lease Payments [Line Items] |  |  |
Total contractual undiscounted payments | £ 74 | £ 167 |

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- Definition The amount of liabilities related to the entity's leases. Lease is a contract, or part of a contract, that conveys the right to use an underlying asset for a period of time in exchange for consideration. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2020-01-01 -Paragraph 47 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2020-en-r&anchor=para_47_b&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The amount of undiscounted operating lease payments to be received. Operating lease is a lease that does not transfer substantially all the risks and rewards incidental to ownership of an underlying asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2020-01-01 -Paragraph 97 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2020-en-r&anchor=para_97&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition Lease effect of discounting. + References No definition available. + Details
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