Derivatives and Currency Exchange Risk Management , Derivative Gains (Losses) Not Designated as Hedging Instruments (Details) - USD ($) $ in Millions	12 Months Ended
	Apr. 26, 2019	Apr. 27, 2018	Apr. 28, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Total	$ 236	$ (226)	$ 54
Currency exchange rate contracts | Other operating expense, net
Derivative Instruments, Gain (Loss) [Line Items]
Total	218	(253)	54
Total return swaps | Other operating expense, net
Derivative Instruments, Gain (Loss) [Line Items]
Total	$ 18	$ 27	$ 0