Share-based compensation plans and shares held in trust - Summary of Share-Based Compensation Expense (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2023 |
Dec. 31, 2022 |
Dec. 31, 2021 |
|
| Disclosure Of Share Based Compensation Expense [Line Items] | |||
| Share-based compensation expense | $ 700 | $ 807 | $ 539 |
| Equity-settled | |||
| Disclosure Of Share Based Compensation Expense [Line Items] | |||
| Share-based compensation expense | $ 700 | $ 807 | $ 539 |