Related party transactions and Directors' remuneration - Disclosure of loans and deposits outstanding (Details) - Key management personnel and connected persons - GBP (£) £ in Millions	Dec. 31, 2025	Dec. 31, 2024
Disclosure of transactions between related parties [line items]
Loans outstanding as at 31 December	£ 12.9	£ 10.8
Deposits outstanding as at 31 December	£ 14.8	£ 9.5

The amounts receivable resulting from related party transactions. [Refer: Total for all related parties [member]]

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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