Expected credit loss measurement - Credit loss expense / release (Narrative) (Detail) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2025 |
Mar. 31, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
|
| Disclosure Of Provision Matrix [Line Items] | |||||
| Credit loss expense / (release) | $ 163 | $ 100 | $ 95 | $ 263 | $ 201 |
| Stage 1 and 2 positions | |||||
| Disclosure Of Provision Matrix [Line Items] | |||||
| Credit loss expense / (release) | 38 | $ (21) | $ (22) | ||
| Stage 1 and 2 positions | Scenario-update-related | |||||
| Disclosure Of Provision Matrix [Line Items] | |||||
| Credit loss expense / (release) | 23 | ||||
| Stage 1 and 2 positions | Expenses in anticipation of a portfolio re-calibration in the large corporate clients segment | |||||
| Disclosure Of Provision Matrix [Line Items] | |||||
| Credit loss expense / (release) | 13 | ||||
| Credit-impaired (stage 3 and purchased credit-impaired) positions | |||||
| Disclosure Of Provision Matrix [Line Items] | |||||
| Credit loss expense / (release) | $ 125 | ||||