v3.5.0.2

Investments (Available-For-Sale Investments With Gross Unrealized Losses) (Details) - USD ($) $ in Millions | Oct. 29, 2016 | Jul. 30, 2016
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Schedule of Investments [Line Items] |  |
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value | $ 22,758 | $ 5,480
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses | (147) | (49)
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value | 675 | 1,208
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses | (4) | (8)
TOTAL, Fair Value | 23,433 | 6,688
TOTAL, Gross Unrealized Losses | (151) | (57)
Publicly traded equity securities |  |
Schedule of Investments [Line Items] |  |
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value | 291 | 188
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses | (53) | (40)
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value | 3 | 0
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses | (1) | 0
TOTAL, Fair Value | 294 | 188
TOTAL, Gross Unrealized Losses | (54) | (40)
Total fixed income securities |  |
Schedule of Investments [Line Items] |  |
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value | 22,467 | 5,292
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses | (94) | (9)
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value | 672 | 1,208
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses | (3) | (8)
TOTAL, Fair Value | 23,139 | 6,500
TOTAL, Gross Unrealized Losses | (97) | (17)
Total fixed income securities | U.S. government securities |  |
Schedule of Investments [Line Items] |  |
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value | 11,766 | 2,414
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses | (33) | (2)
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value | 100 | 0
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses | 0 | 0
TOTAL, Fair Value | 11,866 | 2,414
TOTAL, Gross Unrealized Losses | (33) | (2)
Total fixed income securities | U.S. government agency securities |  |
Schedule of Investments [Line Items] |  |
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value | 596 | 144
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses | (1) | 0
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value | 0 | 0
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses | 0 | 0
TOTAL, Fair Value | 596 | 144
TOTAL, Gross Unrealized Losses | (1) | 0
Total fixed income securities | Non-U.S. government and agency securities |  |
Schedule of Investments [Line Items] |  |
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value | 498 | 61
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses | (1) | 0
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value | 0 | 0
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses | 0 | 0
TOTAL, Fair Value | 498 | 61
TOTAL, Gross Unrealized Losses | (1) | 0
Total fixed income securities | Corporate debt securities |  |
Schedule of Investments [Line Items] |  |
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value | 9,013 | 2,499
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses | (57) | (7)
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value | 572 | 1,208
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses | (3) | (8)
TOTAL, Fair Value | 9,585 | 3,707
TOTAL, Gross Unrealized Losses | (60) | (15)
Total fixed income securities | U.S. agency mortgage-backed securities |  |
Schedule of Investments [Line Items] |  |
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value | 594 | 174
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses | (2) | 0
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value | 0 | 0
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses | 0 | 0
TOTAL, Fair Value | 594 | 174
TOTAL, Gross Unrealized Losses | $ (2) | $ 0

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