Available-for-Sale Debt and Equity Investments - Summary of Available-for-Sale Debt Investments (Details) - USD ($) $ in Millions	May 01, 2021	Jul. 25, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 15,941	$ 17,163
Gross Unrealized Gains	275	454
Gross Unrealized and Credit Losses	(48)
Gross Unrealized Losses		(7)
Fair Value	16,168	17,610
Net unsettled investment sales	262
U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,881	2,614
Gross Unrealized Gains	22	71
Gross Unrealized and Credit Losses	0
Gross Unrealized Losses		0
Fair Value	1,903	2,685
U.S. government agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	167	110
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0
Gross Unrealized Losses		0
Fair Value	167	110
Non-U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3
Gross Unrealized Gains	0
Gross Unrealized and Credit Losses	0
Fair Value	3
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	9,329	11,549
Gross Unrealized Gains	218	334
Gross Unrealized and Credit Losses	(35)
Gross Unrealized Losses		(6)
Fair Value	9,512	11,877
U.S. agency mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,788	1,987
Gross Unrealized Gains	35	49
Gross Unrealized and Credit Losses	(13)
Gross Unrealized Losses		(1)
Fair Value	2,810	2,035
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,333	727
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0
Gross Unrealized Losses		0
Fair Value	1,333	727
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	440	176
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0
Gross Unrealized Losses		0
Fair Value	$ 440	$ 176

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

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- Definition

Debt Securities, Available-For-Sale, Unsettled Sales, Net

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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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Amount, before tax, of unrealized loss 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 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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