Settlement and Other Risk Management - Narrative (Details) - USD ($) $ in Millions |
Jun. 30, 2024 |
Dec. 31, 2023 |
|---|---|---|
| Settlement and Other Risk Management [Abstract] | ||
| Travelers cheques outstanding, notional value | $ 334 | $ 340 |
| Travelers cheques covered by collateral arrangements | $ 268 | $ 272 |