v3.26.1
Credit Risk - Disclosure of measurement uncertainty - Baseline average macroeconomic variables used in the calculation of ECL (Details)
Jun. 30, 2026
Dec. 31, 2025
Baseline    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 39.50% 38.50%
Baseline | GDP | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 0.40% 1.50%
Baseline | GDP | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.70% 2.10%
Baseline | GDP | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.10% 1.10%
Baseline | GDP | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.00% 2.00%
Baseline | GDP | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.40% 1.40%
Baseline | GDP | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.10% 2.00%
Baseline | GDP | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.40% 1.40%
Baseline | GDP | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.10% 2.00%
Baseline | GDP | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.50% 1.40%
Baseline | GDP | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.10% 2.00%
Baseline | Unemployment | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.30% 4.70%
Baseline | Unemployment | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.40% 4.20%
Baseline | Unemployment | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.30% 4.90%
Baseline | Unemployment | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.30% 4.50%
Baseline | Unemployment | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.00% 4.80%
Baseline | Unemployment | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.30% 4.40%
Baseline | Unemployment | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.90% 4.80%
Baseline | Unemployment | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.30% 4.40%
Baseline | Unemployment | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.90% 4.70%
Baseline | Unemployment | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.30% 4.40%
Baseline | HPI | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.30% 1.50%
Baseline | HPI | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.10% 3.20%
Baseline | HPI | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.60% 2.90%
Baseline | HPI | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.10% 1.70%
Baseline | HPI | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.90% 2.50%
Baseline | HPI | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.40% 1.90%
Baseline | HPI | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.00% 4.30%
Baseline | HPI | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.40% 2.60%
Baseline | HPI | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.90% 3.80%
Baseline | HPI | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.40% 2.60%
Baseline | Bank rate | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.10% 4.20%
Baseline | Bank rate | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.40% 3.40%
Baseline | Bank rate | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.30% 3.40%
Baseline | Bank rate | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.30% 3.50%
Baseline | Bank rate | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.30% 3.60%
Baseline | Federal funds rate | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.70% 4.20%
Baseline | Federal funds rate | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.80% 3.40%
Baseline | Federal funds rate | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.80% 3.30%
Baseline | Federal funds rate | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.80% 3.30%
Baseline | Federal funds rate | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.80% 3.50%
Downside 2    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 7.00% 7.00%
Downside 2 | GDP | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting (0.50%) 1.50%
Downside 2 | GDP | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 0.50% 2.10%
Downside 2 | GDP | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting (4.10%) (2.50%)
Downside 2 | GDP | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting (4.30%) (2.70%)
Downside 2 | GDP | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.90% (1.20%)
Downside 2 | GDP | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 0.00% (2.80%)
Downside 2 | GDP | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.70% 2.80%
Downside 2 | GDP | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.10% 1.60%
Downside 2 | GDP | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.00% 1.10%
Downside 2 | GDP | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.60% 2.40%
Downside 2 | Unemployment | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 6.00% 4.70%
Downside 2 | Unemployment | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.50% 4.20%
Downside 2 | Unemployment | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 7.80% 5.80%
Downside 2 | Unemployment | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 8.50% 5.70%
Downside 2 | Unemployment | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 7.80% 7.70%
Downside 2 | Unemployment | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 8.30% 8.00%
Downside 2 | Unemployment | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 6.90% 6.90%
Downside 2 | Unemployment | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 7.20% 7.90%
Downside 2 | Unemployment | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 6.00% 5.70%
Downside 2 | Unemployment | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 6.10% 5.90%
Downside 2 | HPI | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting (12.00%) 1.50%
Downside 2 | HPI | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting (3.10%) 3.20%
Downside 2 | HPI | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting (19.30%) (24.90%)
Downside 2 | HPI | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting (6.30%) (8.20%)
Downside 2 | HPI | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 6.70% (5.10%)
Downside 2 | HPI | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.70% (1.70%)
Downside 2 | HPI | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 9.30% 9.60%
Downside 2 | HPI | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.00% 7.20%
Downside 2 | HPI | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.60% 14.20%
Downside 2 | HPI | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.90% 7.70%
Downside 2 | Bank rate | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.20% 4.20%
Downside 2 | Bank rate | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.10% 2.30%
Downside 2 | Bank rate | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.60% 0.50%
Downside 2 | Bank rate | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.50% 0.40%
Downside 2 | Bank rate | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.50% 1.10%
Downside 2 | Federal funds rate | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.80% 4.20%
Downside 2 | Federal funds rate | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.90% 3.60%
Downside 2 | Federal funds rate | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.30% 2.40%
Downside 2 | Federal funds rate | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.30% 1.40%
Downside 2 | Federal funds rate | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.30% 1.20%
Downside 1    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 12.50% 12.70%
Downside 1 | GDP | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting (0.10%) 1.50%
Downside 1 | GDP | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.10% 2.10%
Downside 1 | GDP | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting (1.60%) (0.70%)
Downside 1 | GDP | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting (1.20%) (0.30%)
Downside 1 | GDP | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.60% 0.10%
Downside 1 | GDP | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.10% (0.40%)
Downside 1 | GDP | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.50% 2.10%
Downside 1 | GDP | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.10% 1.80%
Downside 1 | GDP | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.20% 1.30%
Downside 1 | GDP | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.90% 2.20%
Downside 1 | Unemployment | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.60% 4.70%
Downside 1 | Unemployment | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.00% 4.20%
Downside 1 | Unemployment | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 6.60% 5.30%
Downside 1 | Unemployment | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 6.40% 5.10%
Downside 1 | Unemployment | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 6.40% 6.30%
Downside 1 | Unemployment | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 6.30% 6.20%
Downside 1 | Unemployment | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.90% 5.80%
Downside 1 | Unemployment | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.80% 6.10%
Downside 1 | Unemployment | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.40% 5.20%
Downside 1 | Unemployment | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.20% 5.10%
Downside 1 | HPI | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting (5.40%) 1.50%
Downside 1 | HPI | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting (0.50%) 3.20%
Downside 1 | HPI | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting (9.20%) (11.80%)
Downside 1 | HPI | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting (2.10%) (3.30%)
Downside 1 | HPI | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.30% (1.30%)
Downside 1 | HPI | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.00% 0.10%
Downside 1 | HPI | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 6.10% 6.90%
Downside 1 | HPI | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.70% 4.90%
Downside 1 | HPI | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.30% 8.90%
Downside 1 | HPI | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.70% 5.10%
Downside 1 | Bank rate | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.10% 4.20%
Downside 1 | Bank rate | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.70% 2.90%
Downside 1 | Bank rate | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.50% 2.00%
Downside 1 | Bank rate | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.50% 1.90%
Downside 1 | Bank rate | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.50% 2.40%
Downside 1 | Federal funds rate | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.80% 4.20%
Downside 1 | Federal funds rate | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.20% 3.60%
Downside 1 | Federal funds rate | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.10% 2.80%
Downside 1 | Federal funds rate | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.00% 2.40%
Downside 1 | Federal funds rate | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.00% 2.40%
Upside 2    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 13.70% 14.40%
Upside 2 | GDP | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 0.90% 1.50%
Upside 2 | GDP | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.80% 2.10%
Upside 2 | GDP | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.80% 2.70%
Upside 2 | GDP | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.20% 2.80%
Upside 2 | GDP | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.20% 3.70%
Upside 2 | GDP | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.90% 3.10%
Upside 2 | GDP | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.60% 2.90%
Upside 2 | GDP | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.80% 2.80%
Upside 2 | GDP | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.30% 2.40%
Upside 2 | GDP | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.80% 2.80%
Upside 2 | Unemployment | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.10% 4.70%
Upside 2 | Unemployment | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.20% 4.20%
Upside 2 | Unemployment | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.60% 4.30%
Upside 2 | Unemployment | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.70% 3.90%
Upside 2 | Unemployment | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.10% 4.00%
Upside 2 | Unemployment | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.60% 3.70%
Upside 2 | Unemployment | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.00% 3.90%
Upside 2 | Unemployment | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.60% 3.70%
Upside 2 | Unemployment | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.00% 3.80%
Upside 2 | Unemployment | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.60% 3.70%
Upside 2 | HPI | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.10% 1.50%
Upside 2 | HPI | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.90% 3.20%
Upside 2 | HPI | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 14.20% 11.90%
Upside 2 | HPI | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.30% 6.20%
Upside 2 | HPI | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 6.80% 8.40%
Upside 2 | HPI | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.30% 4.70%
Upside 2 | HPI | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.70% 5.10%
Upside 2 | HPI | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.90% 4.80%
Upside 2 | HPI | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.80% 4.10%
Upside 2 | HPI | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.90% 4.90%
Upside 2 | Bank rate | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.00% 4.20%
Upside 2 | Bank rate | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.80% 3.10%
Upside 2 | Bank rate | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.00% 2.30%
Upside 2 | Bank rate | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.10% 2.30%
Upside 2 | Bank rate | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.30% 2.60%
Upside 2 | Federal funds rate | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.50% 4.20%
Upside 2 | Federal funds rate | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.00% 3.00%
Upside 2 | Federal funds rate | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.00% 2.50%
Upside 2 | Federal funds rate | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.00% 2.50%
Upside 2 | Federal funds rate | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.80% 2.50%
Upside 1    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 27.30% 27.40%
Upside 1 | GDP | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 0.60% 1.50%
Upside 1 | GDP | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.80% 2.10%
Upside 1 | GDP | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.40% 1.90%
Upside 1 | GDP | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.60% 2.40%
Upside 1 | GDP | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.30% 2.60%
Upside 1 | GDP | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.50% 2.60%
Upside 1 | GDP | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.00% 2.20%
Upside 1 | GDP | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.50% 2.40%
Upside 1 | GDP | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 1.90% 1.90%
Upside 1 | GDP | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.50% 2.40%
Upside 1 | Unemployment | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.20% 4.70%
Upside 1 | Unemployment | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.30% 4.20%
Upside 1 | Unemployment | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.90% 4.60%
Upside 1 | Unemployment | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.00% 4.20%
Upside 1 | Unemployment | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.60% 4.40%
Upside 1 | Unemployment | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.00% 4.10%
Upside 1 | Unemployment | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.50% 4.40%
Upside 1 | Unemployment | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.00% 4.10%
Upside 1 | Unemployment | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.50% 4.30%
Upside 1 | Unemployment | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.00% 4.10%
Upside 1 | HPI | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.70% 1.50%
Upside 1 | HPI | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.50% 3.20%
Upside 1 | HPI | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 7.80% 7.40%
Upside 1 | HPI | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.20% 4.00%
Upside 1 | HPI | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 5.40% 5.40%
Upside 1 | HPI | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.80% 3.30%
Upside 1 | HPI | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 2.90% 4.70%
Upside 1 | HPI | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.60% 3.70%
Upside 1 | HPI | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.90% 3.90%
Upside 1 | HPI | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.60% 3.70%
Upside 1 | Bank rate | 2026 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.00% 4.20%
Upside 1 | Bank rate | 2027 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 4.10% 3.20%
Upside 1 | Bank rate | 2028 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.50% 2.80%
Upside 1 | Bank rate | 2029 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.60% 2.80%
Upside 1 | Bank rate | 2030 | UK    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.80% 3.10%
Upside 1 | Federal funds rate | 2026 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.50% 4.20%
Upside 1 | Federal funds rate | 2027 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.30% 3.30%
Upside 1 | Federal funds rate | 2028 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.30% 2.80%
Upside 1 | Federal funds rate | 2029 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.30% 2.80%
Upside 1 | Federal funds rate | 2030 | US    
Disclosure of nature and extent of risks arising from financial instruments [line items]    
Scenario probability weighting 3.30% 3.00%