Settlement Guarantee Management - Collateral (Detail) - USD ($) $ in Millions |
Jun. 30, 2023 |
Sep. 30, 2022 |
|---|---|---|
| Settlement Guarantee Management [Abstract] | ||
| Restricted cash and restricted cash equivalents | $ 2,907 | $ 2,342 |
| Pledged securities at market value | 408 | 213 |
| Letters of credit | 1,717 | 1,582 |
| Guarantees | 1,094 | 950 |
| Total | $ 6,126 | $ 5,087 |