v3.19.1

Income Taxes (Additional Information) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Apr. 27, 2019 | Oct. 27, 2018 | Apr. 28, 2018 | Apr. 27, 2019 | Apr. 28, 2018 | Jul. 28, 2018
Income Tax Contingency [Line Items] |  |  |  |  |  |
Benefit for provision for income taxes | $ (571) |  | $ (562) | $ (1,452) | $ (13,140) |
Tax Cuts and Jobs Act of 2017, provisional tax expense |  |  |  |  |  | $ 10,400
Tax Cuts and Jobs Act, provisional tax expense |  | $ 58 |  | 10,500 |  |
Tax Cuts and Jobs Act, transition tax expense (benefit) |  |  |  | 8,200 |  |
Tax Cuts And Jobs Act, tax expense for foreign withholding tax |  |  |  | 1,200 |  |
Tax Cuts and Jobs Act, re-measurement of net deferred tax assets |  |  |  | 1,100 |  |
Tax Cuts and Jobs Act, transition tax benefit, foreign dividends |  |  |  | 900 |  |
Unrecognized tax benefits | 1,800 |  |  | 1,800 |  |
Unrecognized tax benefits that would impact effective tax rate | 1,600 |  |  | 1,600 |  |
Unrecognized tax benefit that could be reduced in next 12 months | 50 |  |  | 50 |  |
Accounting Standards Update 2014-09 | Difference between Revenue Guidance in Effect before and after Topic 606 |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |
Benefit for provision for income taxes | $ 152 |  |  | $ 152 |  |

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