v3.25.0.1
Intangible assets (Details) - GBP (£)
£ in Thousands
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Reconciliation of changes in intangible assets and goodwill    
Balance at the beginning of period £ 1,018 £ 2,048
Balance at the end of period 132 1,018
IT software    
Reconciliation of changes in intangible assets and goodwill    
Balance at the beginning of period 1,018  
Balance at the end of period 132 1,018
Cost or valuation    
Reconciliation of changes in intangible assets and goodwill    
Balance at the beginning of period 3,865 3,916
Additions   159
Disposals (21) (210)
Balance at the end of period 3,844 3,865
Cost or valuation | IT software    
Reconciliation of changes in intangible assets and goodwill    
Balance at the beginning of period 3,865 3,916
Additions   159
Disposals (21) (210)
Balance at the end of period 3,844 3,865
Amortization    
Reconciliation of changes in intangible assets and goodwill    
Balance at the beginning of period (2,847) (1,868)
Amortization charge 885 1,164
Disposals 20 185
Balance at the end of period (3,712) (2,847)
Amortization | IT software    
Reconciliation of changes in intangible assets and goodwill    
Balance at the beginning of period (2,847) (1,868)
Amortization charge 885 1,164
Disposals 20 185
Balance at the end of period £ (3,712) £ (2,847)