Leases - Movement in lease liabilities (Details) - GBP (£) £ in Thousands	6 Months Ended
Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Lease liabilities
Beginning balance	£ 4,393	£ 5,248
Cash flows	(842)	(1,155)	£ (797)
Acquisition	219	239
Accretion expense	53	61	69
Ending balance	£ 3,823	£ 4,393	5,248
Increase (decrease) due to adoption of IFRS 16
Lease liabilities
Beginning balance			£ 5,976

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.

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

Name:	ifrs-full_LeaseLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant