XML 100 R82.htm IDEA: XBRL DOCUMENT
v3.21.2

Available-for-Sale Debt and Equity Investments - Summary of Available-for-Sale Investments (Details) - USD ($) $ in Millions | Jul. 31, 2021 | Jul. 25, 2020
--- | --- | ---
Schedule of Investments [Line Items] |  |
Amortized Cost | $ 14,978 | $ 17,163
Gross Unrealized Gains | 268 | 454
Gross Unrealized and Credit Losses | (40) |
Gross Unrealized and Credit Losses |  | (7)
Fair Value | 15,206 | 17,610
U.S. government securities |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 1,773 | 2,614
Gross Unrealized Gains | 21 | 71
Gross Unrealized and Credit Losses | 0 |
Gross Unrealized and Credit Losses |  | 0
Fair Value | 1,794 | 2,685
U.S. government agency securities |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 152 | 110
Gross Unrealized Gains | 0 | 0
Gross Unrealized and Credit Losses | 0 |
Gross Unrealized and Credit Losses |  | 0
Fair Value | 152 | 110
Non-U.S. government and agency securities |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 3 |
Gross Unrealized Gains | 0 |
Gross Unrealized and Credit Losses | 0 |
Fair Value | 3 |
Corporate debt securities |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 8,727 | 11,549
Gross Unrealized Gains | 213 | 334
Gross Unrealized and Credit Losses | (30) |
Gross Unrealized and Credit Losses |  | (6)
Fair Value | 8,910 | 11,877
U.S. agency mortgage-backed securities |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 2,838 | 1,987
Gross Unrealized Gains | 34 | 49
Gross Unrealized and Credit Losses | (10) |
Gross Unrealized and Credit Losses |  | (1)
Fair Value | 2,862 | 2,035
Commercial paper |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 1,190 | 727
Gross Unrealized Gains | 0 | 0
Gross Unrealized and Credit Losses | 0 |
Gross Unrealized and Credit Losses |  | 0
Fair Value | 1,190 | 727
Certificates of deposit |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 295 | 176
Gross Unrealized Gains | 0 | 0
Gross Unrealized and Credit Losses | 0 |
Gross Unrealized and Credit Losses |  | 0
Fair Value | $ 295 | $ 176

X
- Definition Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax And Allowance For Credit Loss + References No definition available. + Details
Name: | csco_DebtSecuritiesAvailableForSaleAccumulatedGrossUnrealizedLossBeforeTaxAndAllowanceForCreditLoss
Namespace Prefix: | csco_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563 + Details
Name: | us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563 + Details
Name: | us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestBeforeAllowanceForCreditLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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
Name: | us-gaap_ScheduleOfInvestmentsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_USTreasuryAndGovernmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_USGovernmentAgenciesDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_ForeignGovernmentDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_AssetBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_CommercialPaperMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_CertificatesOfDepositMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |