Settlement Guarantee Management - Collateral (Detail) - USD ($) $ in Millions |
Jun. 30, 2022 |
Sep. 30, 2021 |
|---|---|---|
| Settlement Guarantee Management [Abstract] | ||
| Restricted cash and restricted cash equivalents | $ 2,261 | $ 2,260 |
| Pledged securities at market value | 300 | 254 |
| Letters of credit | 1,622 | 1,518 |
| Guarantees | 706 | 758 |
| Total | $ 4,889 | $ 4,790 |