v3.25.2
Expected credit loss measurement - Comparison of shock factors (Detail) - Baseline
 6 Months Ended
Jun. 30, 2025
2024 | Real GDP growth (annual percentage change) | US  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 2.80%
2024 | Real GDP growth (annual percentage change) | Eurozone  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 0.80%
2024 | Real GDP growth (annual percentage change) | Switzerland  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 1.40%
2024 | Unemployment rate (%, annual average) | US  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 4.00%
2024 | Unemployment rate (%, annual average) | Eurozone  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 6.40%
2024 | Unemployment rate (%, annual average) | Switzerland  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 2.50%
2024 | Fixed income: 10-year government bonds (%, Q4) | USD  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 4.60%
2024 | Fixed income: 10-year government bonds (%, Q4) | EUR  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 2.40%
2024 | Fixed income: 10-year government bonds (%, Q4) | CHF  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 0.30%
2024 | Real estate (annual percentage change, Q4) | US  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 3.80%
2024 | Real estate (annual percentage change, Q4) | Eurozone  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 4.20%
2024 | Real estate (annual percentage change, Q4) | Switzerland  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 0.90%
2025 | Real GDP growth (annual percentage change) | US  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 1.60%
2025 | Real GDP growth (annual percentage change) | Eurozone  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 0.70%
2025 | Real GDP growth (annual percentage change) | Switzerland  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 0.90%
2025 | Unemployment rate (%, annual average) | US  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 4.30%
2025 | Unemployment rate (%, annual average) | Eurozone  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 6.50%
2025 | Unemployment rate (%, annual average) | Switzerland  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 2.90%
2025 | Fixed income: 10-year government bonds (%, Q4) | USD  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 4.20%
2025 | Fixed income: 10-year government bonds (%, Q4) | EUR  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 2.70%
2025 | Fixed income: 10-year government bonds (%, Q4) | CHF  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 0.50%
2025 | Real estate (annual percentage change, Q4) | US  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 2.30%
2025 | Real estate (annual percentage change, Q4) | Eurozone  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 2.70%
2025 | Real estate (annual percentage change, Q4) | Switzerland  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 4.00%
2026 | Real GDP growth (annual percentage change) | US  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 1.20%
2026 | Real GDP growth (annual percentage change) | Eurozone  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 1.00%
2026 | Real GDP growth (annual percentage change) | Switzerland  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 1.40%
2026 | Unemployment rate (%, annual average) | US  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 4.80%
2026 | Unemployment rate (%, annual average) | Eurozone  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 6.60%
2026 | Unemployment rate (%, annual average) | Switzerland  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 2.90%
2026 | Fixed income: 10-year government bonds (%, Q4) | USD  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 4.40%
2026 | Fixed income: 10-year government bonds (%, Q4) | EUR  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 2.80%
2026 | Fixed income: 10-year government bonds (%, Q4) | CHF  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 0.60%
2026 | Real estate (annual percentage change, Q4) | US  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 3.70%
2026 | Real estate (annual percentage change, Q4) | Eurozone  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 3.40%
2026 | Real estate (annual percentage change, Q4) | Switzerland  
Disclosure of Key Macro Economic Variables Used For Expected Credit Loss Model [Line Items]  
Economic forecast 2.50%