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v3.26.1

Comprehensive income - Accumulated Other Comprehensive Income (Loss), Net (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2026 | Jun. 30, 2025 | Jun. 30, 2026 | Jun. 30, 2025
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | $ 27,972 | $ 28,991 | $ 29,177 | $ 29,027
Total other comprehensive income (loss) | (158) | 125 | (369) | 379
Ending balance | 27,946 | 28,525 | 27,946 | 28,525
Investment Securities |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 6 | (6) | 155 | (153)
Total other comprehensive income (loss) | (99) | 67 | (248) | 214
Ending balance | (93) | 61 | (93) | 61
Cash Flow Hedges |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 7 | 7 | 67 | (101)
Total other comprehensive income (loss) | (58) | 56 | (118) | 164
Ending balance | (51) | 63 | (51) | 63
Defined Benefit Plans |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 60 | 96 | 61 | 98
Total other comprehensive income (loss) | (1) | (1) | (2) | (3)
Ending balance | 59 | 95 | 59 | 95
Other |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | (7) | (7) | (6) | (8)
Total other comprehensive income (loss) | 0 | 3 | (1) | 4
Ending balance | (7) | (4) | (7) | (4)
Accumulated Other Comprehensive Income (Loss), Net |  |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |  |
Beginning balance | 66 | 90 | 277 | (164)
Total other comprehensive income (loss) | (158) | 125 | (369) | 379
Ending balance | $ (92) | $ 215 | $ (92) | $ 215

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