Restructuring Charges - Activities Related to Restructuring Reserves (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Oct. 25, 2019	Oct. 26, 2018	Oct. 25, 2019	Oct. 26, 2018
Restructuring Cost and Reserve [Line Items]
Balance at beginning of period			$ 19	$ 6
Net charges	$ 0	$ 0	21	19
Cash payments			(31)	(18)
Other			(4)	0
Balance at end of period	5	7	5	7
May 2019 Restructuring
Restructuring Cost and Reserve [Line Items]
Balance at beginning of period			0
Net charges			21
Cash payments			(19)
Other			0
Balance at end of period	2		2
April 2019 Restructuring
Restructuring Cost and Reserve [Line Items]
Balance at beginning of period			15
Net charges			0
Cash payments			(12)
Other			0
Balance at end of period	3		3
November 2016 Restructuring
Restructuring Cost and Reserve [Line Items]
Balance at beginning of period			4	6
Net charges			0	0
Cash payments			0	(1)
Other			(4)	0
Balance at end of period	0	$ 5	0	$ 5
May 2018 Restructuring
Restructuring Cost and Reserve [Line Items]
Balance at beginning of period			0
Net charges			19
Cash payments			(17)
Other			0
Balance at end of period	$ 2		$ 2