v2.4.0.8

Investments (Summary Of Available-For-Sale Investments) (Detail) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Oct. 26, 2013 | Jul. 27, 2013
Schedule of Investments [Line Items] |  |
Amortized Cost | $ 42,154 | $ 41,930
Gross Unrealized Gains | 819 | 825
Gross Unrealized Losses | (26) | (70)
Fair Value | 42,947 | 42,685
Publicly Traded Equity Securities [Member] |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 1,820 | 2,063
Gross Unrealized Gains | 696 | 738
Gross Unrealized Losses | (2) | (4)
Fair Value | 2,514 | 2,797
Fixed Income Investments [Member] |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 40,334 | 39,867
Gross Unrealized Gains | 123 | 87
Gross Unrealized Losses | (24) | (66)
Fair Value | 40,433 | 39,888
Fixed Income Investments [Member] | US Government Securities[Member] |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 28,603 | 27,814
Gross Unrealized Gains | 37 | 22
Gross Unrealized Losses | (2) | (13)
Fair Value | 28,638 | 27,823
Fixed Income Investments [Member] | US Government Agencies Securities [Member] |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 2,394 | 3,083
Gross Unrealized Gains | 5 | 7
Gross Unrealized Losses | 0 | (1)
Fair Value | 2,399 | 3,089
Fixed Income Investments [Member] | Non-US Government and Agency Securities [Member] |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 907 | 1,094
Gross Unrealized Gains | 3 | 3
Gross Unrealized Losses | (1) | (2)
Fair Value | 909 | 1,095
Fixed Income Investments [Member] | Corporate Debt Securities [Member] |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 7,974 | 7,876
Gross Unrealized Gains | 73 | 55
Gross Unrealized Losses | (21) | (50)
Fair Value | 8,026 | 7,881
Fixed Income Investments [Member] | U.S. agency mortgage-backed Securities |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 456 |
Gross Unrealized Gains | 5 |
Gross Unrealized Losses | 0 |
Fair Value | $ 461 |

X
- 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 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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- Definition Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities. + 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 of unrealized loss before deducting unrealized gain on investments in available-for-sale securities. + 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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