Fair Value Measurements - Schedule of cash equivalents and available-for-sale debt securities by balance sheet classification (Details) - USD ($) $ in Millions	12 Months Ended
	Jul. 31, 2024	Jul. 31, 2023	Jul. 31, 2022
Cash equivalents:
Total cash and cash equivalents	$ 3,609	$ 2,848
Available-for-sale debt securities:
Long-term Investments	131	105
Increases related to tax positions taken during current fiscal year	95	38	$ 31
Level 3
Available-for-sale debt securities:
Upward adjustments to non-marketable equity securities	4	0	$ 54
Cumulative upward adjustments to non-marketable equity securities	75
Fair Value, Measurements, Recurring
Cash equivalents:
Total cash and cash equivalents	2,538	1,888
Available-for-sale debt securities:
Total available-for-sale debt securities	615	1,014
Fair Value, Measurements, Recurring | In cash and cash equivalents
Cash equivalents:
Total cash and cash equivalents	2,538	1,888
Fair Value, Measurements, Recurring | In investments
Available-for-sale debt securities:
Total available-for-sale debt securities	465	814
Fair Value, Measurements, Recurring | In funds receivable and amounts held for customers
Available-for-sale debt securities:
Total available-for-sale debt securities	150	200
Fair Value, Measurements, Recurring | Level 1
Cash equivalents:
Total cash and cash equivalents	2,538	1,888
Available-for-sale debt securities:
Total available-for-sale debt securities	0	0
Fair Value, Measurements, Recurring | Level 1 | In cash and cash equivalents
Cash equivalents:
Total cash and cash equivalents	2,538	1,888
Fair Value, Measurements, Recurring | Level 1 | In investments
Available-for-sale debt securities:
Total available-for-sale debt securities	0	0
Fair Value, Measurements, Recurring | Level 1 | In funds receivable and amounts held for customers
Available-for-sale debt securities:
Total available-for-sale debt securities	0	0
Fair Value, Measurements, Recurring | Level 2
Cash equivalents:
Total cash and cash equivalents	0	0
Available-for-sale debt securities:
Total available-for-sale debt securities	615	1,014
Fair Value, Measurements, Recurring | Level 2 | In cash and cash equivalents
Cash equivalents:
Total cash and cash equivalents	0	0
Fair Value, Measurements, Recurring | Level 2 | In investments
Available-for-sale debt securities:
Total available-for-sale debt securities	465	814
Fair Value, Measurements, Recurring | Level 2 | In funds receivable and amounts held for customers
Available-for-sale debt securities:
Total available-for-sale debt securities	$ 150	$ 200