Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Apr. 30, 2022	Apr. 30, 2022	Apr. 30, 2021	Jul. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term investments	$ 98	$ 98		$ 43
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Upward adjustments to non-marketable equity securities	8	54	$ 17
Cumulative upward adjustments to non-marketable equity securities	$ 71	$ 71