XML 377 R134.htm IDEA: XBRL DOCUMENT v3.23.1
Property, plant and equipment - Additional Information (Details) - GBP (£)
£ in Millions
 12 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Disclosure of detailed information about property, plant and equipment    
Impairments on fixed assets £ 8 £ 0
Freehold buildings | Minimum    
Disclosure of detailed information about property, plant and equipment    
Property, plant and equipment, estimated useful life 50 years  
Freehold buildings | Maximum    
Disclosure of detailed information about property, plant and equipment    
Property, plant and equipment, estimated useful life 100 years  
Vehicles | Minimum    
Disclosure of detailed information about property, plant and equipment    
Property, plant and equipment, estimated useful life 4 years  
Vehicles | Maximum    
Disclosure of detailed information about property, plant and equipment    
Property, plant and equipment, estimated useful life 10 years  
Plant and equipment, including service contract equipment | Minimum    
Disclosure of detailed information about property, plant and equipment    
Property, plant and equipment, estimated useful life 3 years  
Plant and equipment, including service contract equipment | Maximum    
Disclosure of detailed information about property, plant and equipment    
Property, plant and equipment, estimated useful life 10 years  
Office equipment, furniture and fittings | Minimum    
Disclosure of detailed information about property, plant and equipment    
Property, plant and equipment, estimated useful life 3 years  
Office equipment, furniture and fittings | Maximum    
Disclosure of detailed information about property, plant and equipment    
Property, plant and equipment, estimated useful life 10 years