Cash and Cash Equivalents, Investments, and Funds Receivable and Amounts Held for Customers - Investments in funds receivable and amounts held for customers (Details) - USD ($) $ in Millions	Jul. 31, 2023	Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2020
Cash and Cash Equivalents, Investments, and Funds Receivable and Amounts Held for Customers [Abstract]
Restricted cash and restricted cash equivalents	$ 4	$ 201	$ 257	$ 255
Restricted available-for-sale debt securities and funds receivable	416	230	200	200
Total funds receivable and amounts held for customers	$ 420	$ 431	$ 457	$ 455