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Staff Costs - Additional Information (Details) £ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 GBP (£) Director | Dec. 31, 2018 GBP (£) Director
Classes Of Employee Benefits Expense [Abstract] |  |
Number of directors, exercised share options | Director | 1 | 1
Gain on exercise of option | £ | £ 1.4 | £ 4.2

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- Definition Gain on exercise of option. + References No definition available. + Details
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- Definition Number of directors, exercised share options. + References No definition available. + Details
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