Share based payment - Summary of Expense Recognised For Employee Services Received during the Year (Detail) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2025 |
Mar. 31, 2024 |
Mar. 31, 2023 |
|
| Expense from share-based payment transactions [abstract] | |||
| Expense arising from equity-settled share-based payment transactions | $ 2,402 | $ 2,278 | $ 2,512 |
| Total expense arising from share-based payment transactions | $ 2,402 | $ 2,278 | $ 2,512 |