Income Taxes (Additional Information) (Details) $ in Millions	3 Months Ended	6 Months Ended
Jan. 23, 2016 USD ($)	Jan. 23, 2016 USD ($)
Unrecognized Tax Benefits	$ 1,600	$ 1,600
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	1,300	1,300
Unrecognized tax benefit that could be reduced in next 12 months	200	200
IRS and R&D tax credit [Member]
Tax Adjustments, Settlements, and Unusual Provisions	523	523
R&D tax credit- enacted current fiscal year [Member]
Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount	72	72
R&D tax credit- Prior fiscal year [Member]
Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount	84	$ 84
Federal income tax settlement (Year 2008-2010) [Member]
Income Tax Examination, Increase (Decrease) in Liability from Prior Year	563
Income Tax Examination, Liability (Refund) Adjustment from Settlement with Taxing Authority	188
Federal income tax settlement (Year 2008-2010) [Member] \| Include Tax Interest Expense
Tax Adjustments, Settlements, and Unusual Provisions	367
Federal income tax settlement (Year 2008-2010) [Member] \| Reduced tax interest expense upon tax settlement
Tax Adjustments, Settlements, and Unusual Provisions	$ 21

Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to research tax credit.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 10
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-Paragraph 15
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Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

+ References

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-SubTopic 10
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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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