v3.5.0.2

Investments (Summary Of Available-For-Sale Investments) (Details) - USD ($) $ in Millions | Oct. 29, 2016 | Jul. 30, 2016
--- | --- | ---
Schedule of Investments [Line Items] |  |
Amortized Cost | $ 61,968 | $ 57,479
Gross Unrealized Gains | 568 | 703
Gross Unrealized Losses | (151) | (57)
Fair Value | 62,385 | 58,125
Net unsettled available-for-sale investments, purchases | 328 | 654
Total fixed income securities |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 60,743 | 56,268
Gross Unrealized Gains | 222 | 370
Gross Unrealized Losses | (97) | (17)
Fair Value | 60,868 | 56,621
Total fixed income securities | U.S. government securities |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 25,905 | 26,473
Gross Unrealized Gains | 24 | 73
Gross Unrealized Losses | (33) | (2)
Fair Value | 25,896 | 26,544
Total fixed income securities | U.S. government agency securities |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 2,619 | 2,809
Gross Unrealized Gains | 4 | 8
Gross Unrealized Losses | (1) | 0
Fair Value | 2,622 | 2,817
Total fixed income securities | Non-U.S. government and agency securities |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 1,104 | 1,096
Gross Unrealized Gains | 1 | 4
Gross Unrealized Losses | (1) | 0
Fair Value | 1,104 | 1,100
Total fixed income securities | Corporate debt securities |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 29,046 | 24,044
Gross Unrealized Gains | 177 | 263
Gross Unrealized Losses | (60) | (15)
Fair Value | 29,163 | 24,292
Total fixed income securities | U.S. agency mortgage-backed securities |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 2,069 | 1,846
Gross Unrealized Gains | 16 | 22
Gross Unrealized Losses | (2) | 0
Fair Value | 2,083 | 1,868
Publicly traded equity securities |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 1,225 | 1,211
Gross Unrealized Gains | 346 | 333
Gross Unrealized Losses | (54) | (40)
Fair Value | $ 1,517 | $ 1,504

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