v3.10.0.1

Fair Value (Fair Value, Nonrecurring Measurement) (Details) - USD ($) $ in Millions | 3 Months Ended
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Oct. 27, 2018 | Oct. 28, 2017
Fair Value, Measurements, Nonrecurring | Level 3 | Equity securities |  |
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items] |  |
Total gains (losses) for nonrecurring measurements | $ (6) | $ (21)

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- Definition Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items] + References No definition available. + Details
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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228 + Details
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