v2.4.1.9

Investments (Summary Of Available-For-Sale Investments) (Details) (USD $) In Millions, unless otherwise specified | Apr. 25, 2015 | Jul. 26, 2014
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Available-for-sale investments: [Line Items] |  |
Amortized Cost | $ 49,800 us-gaap_AvailableForSaleSecuritiesAmortizedCost | $ 44,619 us-gaap_AvailableForSaleSecuritiesAmortizedCost
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax | 767 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax | 759 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (18)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax | (30)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Fair Value | 50,549 us-gaap_AvailableForSaleSecurities | 45,348 us-gaap_AvailableForSaleSecurities
Total fixed income securities |  |
Available-for-sale investments: [Line Items] |  |
Amortized Cost | 48,472 us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 43,305 us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax | 169 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 111 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (15)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | (20)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Fair Value | 48,626 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 43,396 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Total fixed income securities | U.S. government securities |  |
Available-for-sale investments: [Line Items] |  |
Amortized Cost | 29,364 us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 31,717 us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax | 59 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 29 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (1)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | (12)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Fair Value | 29,422 us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 31,734 us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Total fixed income securities | U.S. government agency securities |  |
Available-for-sale investments: [Line Items] |  |
Amortized Cost | 3,257 us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 1,062 us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax | 6 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 1 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (1)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 0 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Fair Value | 3,262 us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 1,063 us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Total fixed income securities | Non-U.S. government and agency securities |  |
Available-for-sale investments: [Line Items] |  |
Amortized Cost | 1,184 us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 860 us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax | 2 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 2 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | 0 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | (1)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Fair Value | 1,186 us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 861 us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Total fixed income securities | Corporate debt securities |  |
Available-for-sale investments: [Line Items] |  |
Amortized Cost | 13,321 us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 9,092 us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax | 86 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 74 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (13)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | (7)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Fair Value | 13,394 us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 9,159 us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Total fixed income securities | U.S. agency mortgage-backed securities |  |
Available-for-sale investments: [Line Items] |  |
Amortized Cost | 1,346 us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 574 us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax | 16 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 5 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | 0 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 0 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Fair Value | 1,362 us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember | 579 us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_FixedIncomeInvestmentsMember
Publicly traded equity securities [Member] |  |
Available-for-sale investments: [Line Items] |  |
Amortized Cost | 1,328 us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = csco_PubliclytradedequitysecuritiesMember | 1,314 us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = csco_PubliclytradedequitysecuritiesMember
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax | 598 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = csco_PubliclytradedequitysecuritiesMember | 648 us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = csco_PubliclytradedequitysecuritiesMember
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | (3)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = csco_PubliclytradedequitysecuritiesMember | (10)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = csco_PubliclytradedequitysecuritiesMember
Fair Value | $ 1,923 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = csco_PubliclytradedequitysecuritiesMember | $ 1,952 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = csco_PubliclytradedequitysecuritiesMember

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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
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- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + 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 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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