Income Taxes (Additional Information) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Jul. 29, 2017	Jul. 30, 2016	Jul. 25, 2015
Income Tax [Line Items]
Undistributed earnings of certain foreign subsidiaries on which tax is not provided	$ 71,100
Gross income tax benefit attributable to tax incentives	$ 1,300	$ 1,200	$ 1,400
Gross Income Tax Benefit attributable to tax incentives (in dollars per share)	$ 0.25	$ 0.23	$ 0.28
Unrecognized Tax Benefits, reduced	$ 78	$ 457	$ 30
Unrecognized tax benefits that would affect the effective tax rate if realized	1,400
Net interest expense, reduction related to unrecognized tax beneifts	26	55
Penalties, reduction related to unrecognized tax benefits	4	40
Reduction in net interest expense			37
Reduction in penalties			3
Accrual for interest and penalties	186	154	274
Unrecognized tax benefit that could be reduced in next 12 months	100
Tax Year 2016
Income Tax [Line Items]
R&D tax benefit		226
Tax Year 2015
Income Tax [Line Items]
R&D tax benefit		81	138
Tax Year 2014
Income Tax [Line Items]
R&D tax benefit			$ 78
Federal income tax settlement (Year 2008-2010)
Income Tax [Line Items]
Unrecognized Tax Benefits, reduced		563
Accrued income tax interest reduction, tax settlement		63
Federal income tax settlement (Year 2008-2010) | Include reduction of interest expense
Income Tax [Line Items]
Net tax benefit to the income tax provision		$ 367
Federal income tax settlement (Year 2008-2010) | Reduced tax interest expense upon tax settlement
Income Tax [Line Items]
Net tax benefit to the income tax provision	21
Federal
Income Tax [Line Items]
Operating loss carryforwards	719
Tax credit carryforward	18
State and Local Jurisdiction
Income Tax [Line Items]
Operating loss carryforwards	985
Tax credit carryforward	832
Valuation allowance	91
Foreign Tax Authority
Income Tax [Line Items]
Operating loss carryforwards	840
Valuation allowance	132
Tax credit carryforward	$ 20