Derivative Instruments and Hedging Activities - Schedule of Pre-Tax Effect of Changes in Fair Value from Derivative Instruments Not Designated as Hedging Instruments (Details) - Derivatives Not Designated as Hedging Instruments - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
|
| Mortgage derivatives - forward commitments to sell fixed-rate mortgage loans | Mortgage derivatives - forward commitments to sell fixed-rate mortgage loans | ||
| Derivative [Line Items] | ||
| Gain (Loss) Recognized in Consolidated Statements of Income | $ 1 | $ 0 |
| Foreign exchange contracts | ||
| Derivative [Line Items] | ||
| Gain (Loss) Recognized in Consolidated Statements of Income | $ (1) | $ 0 |