Income Taxes (Aggregate Changes in Gross Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
Jul. 28, 2018	Jul. 29, 2017	Jul. 30, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 1,973	$ 1,627	$ 2,029
Additions based on tax positions related to the current year	251	336	255
Additions for tax positions of prior years	84	180	116
Reductions for tax positions of prior years	(129)	(78)	(457)
Settlements	(124)	(43)	(241)
Lapse of statute of limitations	(55)	(49)	(75)
Ending balance	$ 2,000	$ 1,973	$ 1,627

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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