Loans and Related Allowance for Credit Losses, Loan Purchases, Sales, and Transfers (Details) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
|
| Loans and Allowance for Credit Losses, Significant Activity [Abstract] | ||
| Purchases | $ 519 | $ 380 |
| Sales and net transfers (to)/from LHFS | (613) | (843) |
| Total Commercial [Member] | ||
| Loans and Allowance for Credit Losses, Significant Activity [Abstract] | ||
| Purchases | 515 | 379 |
| Sales and net transfers (to)/from LHFS | (617) | (855) |
| Total Consumer [Member] | ||
| Loans and Allowance for Credit Losses, Significant Activity [Abstract] | ||
| Purchases | 4 | 1 |
| Sales and net transfers (to)/from LHFS | $ 4 | $ 12 |