v3.26.1
Financial instruments and risk management - Results of hedge relationships - Narrative (Details) - USD ($)
$ in Millions
12 Months Ended
Jun. 30, 2028
Jun. 30, 2027
Jun. 30, 2026
Jun. 30, 2025
Cash flow hedges | Foreign currency debt risk        
Disclosure of detailed information about financial instruments [line items]        
Loss reported in reserves in respect of hedges of foreign currency borrowing no longer applicable     $ 116 $ 114
Cash flow hedges | Forecast        
Disclosure of detailed information about financial instruments [line items]        
Gain (loss) to income statement $ 14 $ 88    
Hedging reserve | Derivatives | Fair value through income statement        
Disclosure of detailed information about financial instruments [line items]        
Gains (Losses) reclassified from Cash flow hedge reserve into Profit or Loss     7 5
Net investment hedges        
Disclosure of detailed information about financial instruments [line items]        
Net investment hedge reserve     3,127 3,333
Reserve of exchange differences on translation, hedging relationships for which hedge accounting is no longer applied     $ 2,543 $ 2,665