v3.26.1
Pensions and other post-retirement benefits - Disclosure of asset allocation strategy (Details)
Mar. 31, 2026
UK | Pensions  
Disclosure of fair value of plan assets [line items]  
Return-seeking assets 19.00%
Liability-matching assets 81.00%
US | Pensions  
Disclosure of fair value of plan assets [line items]  
Return-seeking assets 30.00%
Liability-matching assets 70.00%
US | Other post-retirement benefits  
Disclosure of fair value of plan assets [line items]  
Return-seeking assets 26.00%
Liability-matching assets 74.00%