Derivative Financial Instruments - Gains and Losses on Hedged Items in Fair Value Hedges (Detail) - Net interest income - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2025 |
Mar. 31, 2024 |
|
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| Gain (Loss) on Derivatives | $ (117) | $ 245 |
| Gain (Loss) on Hedged Items | 134 | (246) |
| Asset-backed securities available-for-sale | Interest rate contracts | ||
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| Gain (Loss) on Derivatives | (177) | 368 |
| Gain (Loss) on Hedged Items | 344 | (194) |
| Deposits | Interest rate contracts | ||
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| Gain (Loss) on Derivatives | 8 | (23) |
| Gain (Loss) on Hedged Items | (31) | (12) |
| Long-term debt | Interest rate contracts | ||
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| Gain (Loss) on Derivatives | 52 | (100) |
| Gain (Loss) on Hedged Items | $ (179) | $ (40) |