v3.26.1
Investments in joint ventures and associates - Disclosure of material interest in joint ventures and associates (Details)
12 Months Ended
Mar. 31, 2026
BritNed Development Limited  
Disclosure of joint ventures [line items]  
Proportion of ownership interest in joint venture 50.00%
Nemo Link Limited  
Disclosure of joint ventures [line items]  
Proportion of ownership interest in joint venture 50.00%