Investments - Summary of Available-for-Sale Debt Investments (Details) - USD ($) $ in Millions	Apr. 25, 2026	Jul. 26, 2025
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 9,225	$ 7,473
Gross Unrealized Gains	6	15
Gross Unrealized and Credit Losses	(51)	(107)
Fair Value	9,180	7,381
U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,716	1,971
Gross Unrealized Gains	2	2
Gross Unrealized and Credit Losses	(6)	(12)
Fair Value	1,712	1,961
U.S. government agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	41	67
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	41	67
Non-U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	400	458
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	400	458
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,791	3,138
Gross Unrealized Gains	4	13
Gross Unrealized and Credit Losses	(37)	(61)
Fair Value	2,758	3,090
Mortgage- and asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	211	320
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	(8)	(34)
Fair Value	203	286
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,731	950
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	2,731	950
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,335	569
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	$ 1,335	$ 569

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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