Average balance of securities lending.

No definition available.

Name:	csco_AverageBalanceOfSecuritiesLending
Namespace Prefix:	csco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Fair value of securities received as collateral that can be resold or repledged percentage.

+ References

No definition available.

+ Details

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Namespace Prefix:	csco_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Funding Obligation, Amount

+ References

No definition available.

+ Details

Name:	csco_FundingObligationAmount
Namespace Prefix:	csco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Secured Lending Transactions Outstanding

+ References

No definition available.

+ Details

Name:	csco_SecuredLendingTransactionsOutstanding
Namespace Prefix:	csco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Variable Interest Entity, Number Of Entities Required To Be Consolidated

+ References

No definition available.

+ Details

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- Definition

Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents the amount of loss recognized for other than temporary impairments (OTTI) of investments in debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.M)
-URI http://asc.fasb.org/extlink&oid=65877573&loc=d3e87990-122713

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=SL6284393-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=SL6284393-111563

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Details

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Investments (Additional Information) (Details) entity in Millions	3 Months Ended		9 Months Ended
	Apr. 28, 2018 USD ($) entity	Apr. 29, 2017 USD ($)	Apr. 28, 2018 USD ($) entity	Apr. 29, 2017 USD ($)	Jul. 29, 2017 USD ($)
Schedule of Investments [Line Items]
Impairment charges of available-for-sale investments	$ 26,000,000	$ 73,000,000	$ 52,000,000	$ 73,000,000
Other than temporary impairment, credit losses recognized in earnings, credit losses on debt securities held	0		0
Average daily balance of securities lending			$ 300,000,000	$ 800,000,000
Fair value of securities received as collateral that can be resold or repledged, percentage (at least)			102.00%
Secured lending transactions outstanding	$ 0		$ 0		$ 0
Number of variable interest entities required to be consolidated (entity) \| entity	0		0
Investments in privately held companies	$ 969,000,000		$ 969,000,000		$ 983,000,000
Funding commitments	212,000,000		212,000,000
Variable Interest Entity, Not Primary Beneficiary
Schedule of Investments [Line Items]
Investments in privately held companies	$ 511,000,000		$ 511,000,000