v3.19.1

Available-for-Sale Debt Investments and Equity Investments (Summary of Available-for-sale Debt Investments and Equity Investments) (Details) - USD ($) $ in Millions | Apr. 27, 2019 | Jul. 28, 2018
--- | --- | ---
Investments, Debt and Equity Securities [Abstract] |  |
Available-for-sale debt investments | $ 24,387 | $ 37,009
Marketable equity securities | 5 | 605
Total investments | 24,392 | 37,614
Non-marketable equity securities included in other assets (1) | 1,135 | 978
Equity method investments included in other assets | 115 | 118
Total | 25,642 | 38,710
Debt Securities, Available-for-sale [Line Items] |  |
Non-marketable equity securities included in other assets | 1,135 | $ 978
Net Asset Value (NAV) | Private equity funds |  |
Investments, Debt and Equity Securities [Abstract] |  |
Non-marketable equity securities included in other assets (1) | 600 |
Debt Securities, Available-for-sale [Line Items] |  |
Non-marketable equity securities included in other assets | $ 600 |

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