The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2020-01-01
-Paragraph 45
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2020-en-r&anchor=para_45&doctype=Standard
-URIDate 2020-01-01

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2020-01-01
-Paragraph B13
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2020-en-r&anchor=para_B13_a&doctype=Appendix&subtype=B
-URIDate 2020-01-01

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 54
-Subparagraph i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_54_i&doctype=Standard
-URIDate 2020-01-01

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Financial Instruments Risk Management - Schedule of Financial Assets Subject to Fixed or Variable Interest Rates (Details) - GBP (£) £ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Financial Instruments By Type Of Interest Rate [Line Items]
Cash and cash equivalents	£ 87,356	£ 51,962	£ 76,972	£ 86,703
Financial Assets at Short Term Fixed Rates [member]
Disclosure Of Financial Instruments By Type Of Interest Rate [Line Items]
Cash and cash equivalents	48,432	41,827
Financial Assets at Variable Rates [member]
Disclosure Of Financial Instruments By Type Of Interest Rate [Line Items]
Cash and cash equivalents	5,470	7,108
Non-Interest Bearing Cash Balances [member]
Disclosure Of Financial Instruments By Type Of Interest Rate [Line Items]
Cash and cash equivalents	£ 33,454	£ 3,027