Cash and Cash Equivalents, Investments, and Funds Held for Customers - Classified by the stated maturity date (Details) - USD ($) $ in Millions	Oct. 31, 2020	Jul. 31, 2020
Amortized Cost
Due within one year	$ 371	$ 389
Due within two years	246	256
Due within three years	187	137
Due after three years	9	18
Total available-for-sale debt securities	813	800
Fair Value
Due within one year	372	390
Due within two years	250	261
Due within three years	188	139
Due after three years	9	18
Total available-for-sale debt securities	819	808
Long-term investments	$ 28	$ 19