Financial Instrument Risk - Maximum Exposure to Credit Risk (Details) - Credit risk - GBP (£) £ in Thousands	Jun. 30, 2018	Jun. 30, 2017
Disclosure of credit risk exposure [line items]
Total	£ 67,400	£ 65,065
Cash and cash equivalents
Disclosure of credit risk exposure [line items]
Total	15,048	23,571
Trade and other receivables
Disclosure of credit risk exposure [line items]
Total	£ 52,352	£ 41,494

The amount that best represents the maximum exposure to credit risk without taking into account any collateral held or other credit enhancements (for example, netting agreements that do not qualify for offset in accordance with IAS 32). [Refer: Credit risk [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2018-01-01
-Name IFRS
-Number 7
-IssueDate 2017-01-01
-Paragraph 35K
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_35K_a&doctype=Standard
-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2018-01-01
-Name IFRS
-Number 7
-IssueDate 2017-01-01
-Paragraph 36
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_36_a&doctype=Standard&book=B
-URIDate 2017-03-09

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