Long-Term Obligations and Commitments - Other Long-Term Obligations (Details) - USD ($) $ in Millions	Jul. 31, 2020	Jul. 31, 2019
Long-Term Obligations and Commitments [Abstract]
Long-term income tax liabilities	$ 10	$ 89
Total deferred rent	0	47
Total dividend payable	12	11
Other	30	12
Total long-term obligations	52	159
Less current portion (included in other current liabilities)	(10)	(14)
Long-term obligations due after one year	$ 42	$ 145