Commitments and Contingencies - Schedule of Purchase Commitments (Details) - USD ($) $ in Millions	May 01, 2021	Jul. 25, 2020
Commitments and Contingencies Disclosure [Abstract]
Less than 1 year	$ 6,461	$ 3,994
1 to 3 years	1,615	412
3 to 5 years	1,733	0
Total	$ 9,809	$ 4,406

Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Four And Five

No definition available.

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Period Type:	instant

- Definition

Unrecorded Unconditional Purchase Obligation, Due in Rolling Year Two And Three

+ References

No definition available.

+ Details

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Namespace Prefix:	csco_
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Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121559207&loc=d3e25336-109308

+ Details

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Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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