Available-for-Sale Debt Investments and Equity Investments (Additional Information) (Details) entity in Millions |
3 Months Ended | ||
|---|---|---|---|
|
Oct. 27, 2018
USD ($)
entity
|
Oct. 28, 2017
USD ($)
|
Jul. 28, 2018
USD ($)
|
|
| Schedule of Investments [Line Items] | |||
| Impairment charges of available-for-sale investments | $ 0 | $ 0 | |
| Average daily balance of securities lending | $ 500,000,000 | $ 500,000,000 | |
| Fair value of securities received as collateral that can be resold or repledged, percentage (at least) | 102.00% | ||
| Secured lending transactions outstanding | $ 0 | $ 0 | |
| Number of variable interest entities required to be consolidated (entity) | entity | 0 | ||
| Investments in privately held companies | $ 1,200,000,000 | ||
| Funding commitments | 204,000,000 | ||
| Variable Interest Entity, Not Primary Beneficiary | |||
| Schedule of Investments [Line Items] | |||
| Investments in privately held companies | $ 670,000,000 | ||