Report of Directors Corporate Governance - Payments to Past Directors (Details) - Former Directors	12 Months Ended
Dec. 31, 2017 GBP (£)
Disclosure of transactions between related parties [line items]
Payments to key management personnel in excess of minimum threshold	£ 0
Key management personnel, threshold minimum	£ 50,000

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

No definition available.

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Period Type:	duration