Derivative Instruments - Effect of Derivative Instruments Designated as Fair Value Hedges (Details) - Interest and other income (loss), net - Interest rate derivatives - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jan. 23, 2021	Jan. 25, 2020	Jan. 23, 2021	Jan. 25, 2020
Derivative [Line Items]
Hedged items	$ 14	$ 7	$ 33	$ (14)
Derivatives designated as hedging instruments	(14)	(6)	(34)	16
Total	$ 0	$ 1	$ (1)	$ 2

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
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- Definition

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959

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