Deferred Tax Assets and Liabilities - Composition of Net Deferred Tax Asset (Details) - GBP (£) £ in Thousands	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Income Taxes [Abstract]
Deferred tax assets	£ 2,488	£ 867
Deferred tax liabilities	(2,832)	(2,586)
Net deferred tax	£ (344)	£ (1,719)	£ (424)

The amounts of income taxes recoverable in future periods in respect of: (a) deductible temporary differences; (b) the carryforward of unused tax losses; and (c) the carryforward of unused tax credits. [Refer: Temporary differences [member]; Unused tax credits [member]; Unused tax losses [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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