Commitments and Contingencies Contingencies (Details) - GBP (£) £ in Millions	1 Months Ended
Dec. 31, 2021	Apr. 30, 2021
Loss Contingencies [Line Items]
Loss Contingency, Amount Withheld by Counterparty		£ 50
Loss Contingency, Amount Remitted by Counterparty	£ 47

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

No definition available.

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