Investments - Summary of Available-for-Sale Debt Investments (Details) - USD ($) $ in Millions	Apr. 27, 2024	Jul. 29, 2023
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 9,884	$ 16,199
Gross Unrealized Gains	1	18
Gross Unrealized and Credit Losses	(478)	(625)
Fair Value	9,407	15,592
U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,411	3,587
Gross Unrealized Gains	0	1
Gross Unrealized and Credit Losses	(49)	(62)
Fair Value	2,362	3,526
U.S. government agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	248	428
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	(3)	(5)
Fair Value	245	423
Non-U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	390	364
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	(1)
Fair Value	390	363
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,985	7,238
Gross Unrealized Gains	1	3
Gross Unrealized and Credit Losses	(198)	(327)
Fair Value	3,788	6,914
U.S. agency mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,058	2,421
Gross Unrealized Gains	0	14
Gross Unrealized and Credit Losses	(228)	(230)
Fair Value	1,830	2,205
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	563	1,484
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	563	1,484
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	229	677
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	$ 229	$ 677

Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax And Allowance For Credit Loss

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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