Income Taxes - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended			24 Months Ended
	Jul. 25, 2020	Jul. 27, 2019	Jul. 28, 2018	Jul. 27, 2019
Income Tax [Line Items]
Tax Cuts and Jobs Act, transition tax expense (benefit)				$ 11,300
Tax Cuts and Jobs Act, tax expense for transition tax on accumulated foreign earnings				9,000
Tax Cuts and Jobs Act, tax expense for foreign withholding tax				1,200
Tax Cuts and Jobs Act, re-measurement of net deferred tax assets				1,100
Undistributed earnings of certain foreign subsidiaries on which tax is not provided	$ 6,800
Unrecognized deferred income tax liability	706
Gross income tax benefit attributable to tax incentives		$ 300	$ 900
Gross income tax benefit attributable to tax incentives (in dollars per share)		$ 0.08	$ 0.19
Unrecognized tax benefits that would affect the effective tax rate if realized	2,200
Net interest expense, reduction related to unrecognized tax benefits	104	$ 30	$ 10
Increase in unrecognized tax benefits for prior year tax positions	554	84	84
Accrual for interest and penalties	340	$ 220	$ 180	$ 220
Unrecognized tax benefit that could be reduced in next 12 months	150
Domestic Tax Authority
Income Tax [Line Items]
Operating loss carryforwards	405
Tax credit carryforward	10
State and Local Jurisdiction
Income Tax [Line Items]
Operating loss carryforwards	1,200
Tax credit carryforward	1,200
Tax credit carryforward, valuation allowance	541
Foreign Tax Authority
Income Tax [Line Items]
Operating loss carryforwards	644
Operating loss carryforwards, valuation allowance	98
Tax credit carryforward	5
Internal Revenue Service (IRS)
Income Tax [Line Items]
Income tax examination, adjustment from settlement	102
Internal Revenue Service (IRS) | Interest expense
Income Tax [Line Items]
Income tax examination, adjustment from settlement	$ 4