v2.4.0.6

Investments (Available-For-Sale Investments With Gross Unrealized Losses) (Detail) (USD $) In Millions, unless otherwise specified | Jul. 28, 2012 | Jul. 30, 2011
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Schedule of Investments [Line Items] |  |
Fair value of investment securities with unrealized losses less than 12 months | $ 6,127 | $ 3,845
Gross unrealized losses, less than 12 months | (12) | (16)
Fair value of investment securities with unrealized losses12 months or greater | 34 | 161
Gross unrealized losses, 12 months or greater | (3) | (6)
Fair value of investment securities with unrealized losses | 6,161 | 4,006
Total gross unrealized losses | (15) | (22)
Publicly Traded Equity Securities |  |
Schedule of Investments [Line Items] |  |
Fair value of investment securities with unrealized losses less than 12 months | 167 | 112
Gross unrealized losses, less than 12 months | (8) | (12)
Fair value of investment securities with unrealized losses12 months or greater | 20 |
Gross unrealized losses, 12 months or greater | (3) |
Fair value of investment securities with unrealized losses | 187 | 112
Total gross unrealized losses | (11) | (12)
Total Fixed Income Securities |  |
Schedule of Investments [Line Items] |  |
Fair value of investment securities with unrealized losses less than 12 months | 5,960 | 3,733
Gross unrealized losses, less than 12 months | (4) | (4)
Fair value of investment securities with unrealized losses12 months or greater | 14 | 161
Gross unrealized losses, 12 months or greater |  | (6)
Fair value of investment securities with unrealized losses | 5,974 | 3,894
Total gross unrealized losses | (4) | (10)
Total Fixed Income Securities | U.S. Government Agency Securities |  |
Schedule of Investments [Line Items] |  |
Fair value of investment securities with unrealized losses less than 12 months | 5,357 | 2,310
Gross unrealized losses, less than 12 months | (1) | (1)
Fair value of investment securities with unrealized losses | 5,357 | 2,310
Total gross unrealized losses | (1) | (1)
Total Fixed Income Securities | Non-U.S. Government And Agency Securities |  |
Schedule of Investments [Line Items] |  |
Fair value of investment securities with unrealized losses less than 12 months |  | 875
Gross unrealized losses, less than 12 months |  | (1)
Fair value of investment securities with unrealized losses |  | 875
Total gross unrealized losses |  | (1)
Total Fixed Income Securities | Corporate Debt Securities |  |
Schedule of Investments [Line Items] |  |
Fair value of investment securities with unrealized losses less than 12 months | 603 | 548
Gross unrealized losses, less than 12 months | (3) | (2)
Fair value of investment securities with unrealized losses12 months or greater | 14 | 56
Gross unrealized losses, 12 months or greater |  | (2)
Fair value of investment securities with unrealized losses | 617 | 604
Total gross unrealized losses | (3) | (4)
Total Fixed Income Securities | Asset-Backed Securities |  |
Schedule of Investments [Line Items] |  |
Fair value of investment securities with unrealized losses12 months or greater |  | 105
Gross unrealized losses, 12 months or greater |  | (4)
Fair value of investment securities with unrealized losses |  | 105
Total gross unrealized losses |  | $ (4)

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- Definition This item represents the excess of amortized cost basis over fair value of securities in a loss position and which are categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 03-1 -Paragraph 21 -Subparagraph a -Clause 2 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 17 -Subparagraph a -Clause 2 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 03-1 -Paragraph 21 -Subparagraph a(2) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 17 -Subparagraph a(1) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27290-111563 + Details
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- Definition This item represents the excess of amortized cost basis over fair value of securities that have been in a loss position for less than twelve months for those securities which are categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 17 -Subparagraph a -Clause 2 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27337-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27290-111563 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 03-1 -Paragraph 21 -Subparagraph a -Clause 2 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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