v3.19.1

Fair Value (Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - USD ($) $ in Millions | Apr. 27, 2019 | Jul. 28, 2018
--- | --- | ---
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | $ 24,387 | $ 37,009
Marketable equity securities | 5 | 605
Derivative assets | 36 | 2
Derivative liabilities | 20 | 74
U.S. government securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 1,452 | 7,275
U.S. government agency securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 263 | 727
Non-U.S. government and agency securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments |  | 208
Corporate debt securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 21,232 | 27,364
Fair Value, Measurements, Recurring |  |
Fair Value Measurements [Line Items] |  |
Marketable equity securities | 5 | 605
Derivative assets | 36 | 2
Total | 32,711 | 44,506
Derivative liabilities | 20 | 74
Total | 20 | 74
Fair Value, Measurements, Recurring | U.S. government securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 1,452 | 7,275
Fair Value, Measurements, Recurring | U.S. government agency securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 263 | 727
Fair Value, Measurements, Recurring | Non-U.S. government and agency securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 0 | 208
Fair Value, Measurements, Recurring | Corporate debt securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 21,232 | 27,364
Fair Value, Measurements, Recurring | U.S. agency mortgage-backed securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 1,440 | 1,435
Fair Value, Measurements, Recurring | Money market funds |  |
Fair Value Measurements [Line Items] |  |
Cash equivalents: | 8,283 | 6,890
Fair Value, Measurements, Recurring | Level 1 |  |
Fair Value Measurements [Line Items] |  |
Marketable equity securities | 5 | 605
Derivative assets | 0 | 0
Total | 8,288 | 7,495
Derivative liabilities | 0 | 0
Total | 0 | 0
Fair Value, Measurements, Recurring | Level 1 | U.S. government securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 0 | 0
Fair Value, Measurements, Recurring | Level 1 | U.S. government agency securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 0 | 0
Fair Value, Measurements, Recurring | Level 1 | Non-U.S. government and agency securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 0 | 0
Fair Value, Measurements, Recurring | Level 1 | Corporate debt securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 0 | 0
Fair Value, Measurements, Recurring | Level 1 | U.S. agency mortgage-backed securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 0 | 0
Fair Value, Measurements, Recurring | Level 1 | Money market funds |  |
Fair Value Measurements [Line Items] |  |
Cash equivalents: | 8,283 | 6,890
Fair Value, Measurements, Recurring | Level 2 |  |
Fair Value Measurements [Line Items] |  |
Marketable equity securities | 0 | 0
Derivative assets | 36 | 2
Total | 24,423 | 37,011
Derivative liabilities | 20 | 74
Total | 20 | 74
Fair Value, Measurements, Recurring | Level 2 | U.S. government securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 1,452 | 7,275
Fair Value, Measurements, Recurring | Level 2 | U.S. government agency securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 263 | 727
Fair Value, Measurements, Recurring | Level 2 | Non-U.S. government and agency securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 0 | 208
Fair Value, Measurements, Recurring | Level 2 | Corporate debt securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 21,232 | 27,364
Fair Value, Measurements, Recurring | Level 2 | U.S. agency mortgage-backed securities |  |
Fair Value Measurements [Line Items] |  |
Available-for-sale debt investments | 1,440 | 1,435
Fair Value, Measurements, Recurring | Level 2 | Money market funds |  |
Fair Value Measurements [Line Items] |  |
Cash equivalents: | $ 0 | $ 0

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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References No definition available. + Details
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