Notes Receivable and Allowances for Credit Losses (Details) - USD ($) $ in Millions	3 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Jul. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans purchased from originating bank partner, principal balance	$ 650	$ 279
Commitment to purchase, amount originated before period end	$ 22
Period of suspended accrued interest past due	120 days
Period past due considered delinquent	1 day
Minimum commitment to sell participation interest in unsecured term loans, cumulatively	$ 350
Notes receivable, remaining amount held for sale	248
Notes receivable held for sale	10		$ 3
Loans sold	106	$ 35
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Minimum commitment to sell participation interest in unsecured term loans, monthly	$ 8
Term of commitment	4 years
Small Business Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable, net	$ 1,000		$ 912