Financial Instruments and Fair Value Measurements - Contractual Maturities of Debt Investments (Detail) $ in Millions	Oct. 25, 2019 USD ($)
Investments Debt And Equity Securities [Abstract]
Due in one year or less, Amortized Cost	$ 464
Due after one year through five years, Amortized Cost	122
Due after five years through ten years, Amortized Cost	5
Total, Amortized Cost	591
Due in one year or less, Estimated Fair Value	464
Due after one year through five years, Estimated Fair Value	123
Due after five years through ten years, Estimated Fair Value	5
Total, Estimated Fair Value	$ 592