Acquisitions - Fair Value Measurement, Contingent Consideration, Significant Unobservable Inputs (Details) $ in Millions	Jan. 24, 2020 USD ($)	Oct. 25, 2019 USD ($)	Apr. 26, 2019 USD ($)	Jan. 25, 2019 USD ($)	Oct. 26, 2018 USD ($)	Apr. 27, 2018 USD ($)
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Contingent consideration, fair value	$ 304	$ 260	$ 222	$ 148	$ 203	$ 173
Revenue and other performance-based payments | Recurring | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Contingent consideration, fair value	$ 123
Revenue and other performance-based payments | Minimum | Recurring | Level 3 | Discount rate
Fair Value Inputs
Contingent consideration, significant unobservable inputs	0.115
Revenue and other performance-based payments | Minimum | Recurring | Level 3 | Probability of payment
Fair Value Inputs
Contingent consideration, significant unobservable inputs	0.30
Revenue and other performance-based payments | Maximum | Recurring | Level 3 | Discount rate
Fair Value Inputs
Contingent consideration, significant unobservable inputs	0.325
Revenue and other performance-based payments | Maximum | Recurring | Level 3 | Probability of payment
Fair Value Inputs
Contingent consideration, significant unobservable inputs	1
Product development and other milestone-based payments | Recurring | Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Contingent consideration, fair value	$ 181
Product development and other milestone-based payments | Recurring | Level 3 | Discount rate
Fair Value Inputs
Contingent consideration, significant unobservable inputs	0.055
Product development and other milestone-based payments | Minimum | Recurring | Level 3 | Probability of payment
Fair Value Inputs
Contingent consideration, significant unobservable inputs	0.75
Product development and other milestone-based payments | Maximum | Recurring | Level 3 | Probability of payment
Fair Value Inputs
Contingent consideration, significant unobservable inputs	1