v2.4.0.8

Investments (Available-For-Sale Investments With Gross Unrealized Losses) (Detail) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 12 Months Ended
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Oct. 26, 2013 | Jul. 27, 2013
Schedule of Investments [Line Items] |  |
Available-for-sale Securities with Unrealized Losses Less than 12 Months, Fair Value | $ 6,146 | $ 12,573
Gross Unrealized Losses, Less than 12 Months | (26) | (70)
Available-for-sale Securities with Unrealized Losses 12 Months or Longer, Fair Value | 23 | 4
Gross Unrealized Losses, 12 Months or Longer | 0 | 0
Available-for-sale Investments with Unrealized Losses, Fair Value | 6,169 | 12,577
Total Gross Unrealized Losses | (26) | (70)
Publicly Traded Equity Securities [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-sale Securities with Unrealized Losses Less than 12 Months, Fair Value | 45 | 278
Gross Unrealized Losses, Less than 12 Months | (2) | (4)
Available-for-sale Securities with Unrealized Losses 12 Months or Longer, Fair Value | 0 | 0
Gross Unrealized Losses, 12 Months or Longer | 0 | 0
Available-for-sale Investments with Unrealized Losses, Fair Value | 45 | 278
Total Gross Unrealized Losses | (2) | (4)
Total Fixed Income Securities [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-sale Securities with Unrealized Losses Less than 12 Months, Fair Value | 6,101 | 12,295
Gross Unrealized Losses, Less than 12 Months | (24) | (66)
Available-for-sale Securities with Unrealized Losses 12 Months or Longer, Fair Value | 23 | 4
Gross Unrealized Losses, 12 Months or Longer | 0 | 0
Available-for-sale Investments with Unrealized Losses, Fair Value | 6,124 | 12,299
Total Gross Unrealized Losses | (24) | (66)
Total Fixed Income Securities [Member] | US Government Securities[Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-sale Securities with Unrealized Losses Less than 12 Months, Fair Value | 3,303 | 7,865
Gross Unrealized Losses, Less than 12 Months | (2) | (13)
Available-for-sale Securities with Unrealized Losses 12 Months or Longer, Fair Value | 8 | 0
Gross Unrealized Losses, 12 Months or Longer | 0 | 0
Available-for-sale Investments with Unrealized Losses, Fair Value | 3,311 | 7,865
Total Gross Unrealized Losses | (2) | (13)
Total Fixed Income Securities [Member] | US Government Agencies Securities [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-sale Securities with Unrealized Losses Less than 12 Months, Fair Value | 201 | 294
Gross Unrealized Losses, Less than 12 Months | 0 | (1)
Available-for-sale Securities with Unrealized Losses 12 Months or Longer, Fair Value | 0 | 0
Gross Unrealized Losses, 12 Months or Longer | 0 | 0
Available-for-sale Investments with Unrealized Losses, Fair Value | 201 | 294
Total Gross Unrealized Losses | 0 | (1)
Total Fixed Income Securities [Member] | Non-US Government and Agency Securities [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-sale Securities with Unrealized Losses Less than 12 Months, Fair Value | 208 | 432
Gross Unrealized Losses, Less than 12 Months | (1) | (2)
Available-for-sale Securities with Unrealized Losses 12 Months or Longer, Fair Value | 2 | 0
Gross Unrealized Losses, 12 Months or Longer | 0 | 0
Available-for-sale Investments with Unrealized Losses, Fair Value | 210 | 432
Total Gross Unrealized Losses | (1) | (2)
Total Fixed Income Securities [Member] | Corporate Debt Securities [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-sale Securities with Unrealized Losses Less than 12 Months, Fair Value | 2,357 | 3,704
Gross Unrealized Losses, Less than 12 Months | (21) | (50)
Available-for-sale Securities with Unrealized Losses 12 Months or Longer, Fair Value | 13 | 4
Gross Unrealized Losses, 12 Months or Longer | 0 | 0
Available-for-sale Investments with Unrealized Losses, Fair Value | 2,370 | 3,708
Total Gross Unrealized Losses | (21) | (50)
Total Fixed Income Securities [Member] | U.S. agency mortgage-backed Securities |  |
Schedule of Investments [Line Items] |  |
Available-for-sale Securities with Unrealized Losses Less than 12 Months, Fair Value | 32 |
Gross Unrealized Losses, Less than 12 Months | 0 |
Available-for-sale Securities with Unrealized Losses 12 Months or Longer, Fair Value | 0 |
Gross Unrealized Losses, 12 Months or Longer | 0 |
Available-for-sale Investments with Unrealized Losses, Fair Value | 32 |
Total Gross Unrealized Losses | $ 0 |

X
- Definition Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer. + 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=27724398&loc=d3e27290-111563 + Details
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- Definition Amount of unrealized loss on 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 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + 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 Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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- Definition Amount of unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months. + References Reference 1: 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=27724398&loc=d3e27337-111563 Reference 2: 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=27724398&loc=d3e27290-111563 + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months. + References Reference 1: 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=27724398&loc=d3e27337-111563 Reference 2: 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=27724398&loc=d3e27290-111563 + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer. + References Reference 1: 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=27724398&loc=d3e27337-111563 Reference 2: 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=27724398&loc=d3e27290-111563 + Details
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