Accumulated Other Comprehensive Loss - Changes in AOCI (Details) - USD ($)	3 Months Ended				6 Months Ended
	Oct. 30, 2020	Jul. 31, 2020	Oct. 25, 2019	Jul. 26, 2019	Oct. 30, 2020	Oct. 25, 2019
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 50,443,000,000	$ 50,872,000,000	$ 50,497,000,000	$ 50,212,000,000	$ 50,872,000,000	$ 50,212,000,000
Other comprehensive (loss) income	(60,000,000)	(217,000,000)	(127,000,000)	227,000,000	(277,000,000)	100,000,000
Ending balance	50,316,000,000	50,443,000,000	50,719,000,000	50,497,000,000	50,316,000,000	50,719,000,000
Total Accumulated Other Comprehensive (Loss) Income
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(3,782,000,000)	(3,560,000,000)	(2,484,000,000)	(2,711,000,000)	(3,560,000,000)	(2,711,000,000)
Other comprehensive income (loss) before reclassifications					(280,000,000)	153,000,000
Reclassifications					(3,000,000)	(53,000,000)
Other comprehensive (loss) income	(61,000,000)	(222,000,000)	(127,000,000)	227,000,000	(283,000,000)	100,000,000
Ending balance	(3,843,000,000)	(3,782,000,000)	(2,611,000,000)	(2,484,000,000)	(3,843,000,000)	(2,611,000,000)
Unrealized Gain (Loss) on Investment Securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance		0		(45,000,000)	0	(45,000,000)
Other comprehensive income (loss) before reclassifications					114,000,000	68,000,000
Reclassifications					(1,000,000)	5,000,000
Other comprehensive (loss) income					113,000,000	73,000,000
Ending balance	113,000,000		28,000,000		113,000,000	28,000,000
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)					31,000,000	1,000,000
Reclassifications, tax expense (benefit)					0	(2,000,000)
Cumulative Translation Adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance		(2,210,000,000)		(1,383,000,000)	(2,210,000,000)	(1,383,000,000)
Other comprehensive income (loss) before reclassifications					1,255,000,000	(148,000,000)
Reclassifications					0	0
Other comprehensive (loss) income					1,255,000,000	(148,000,000)
Ending balance	(955,000,000)		(1,531,000,000)		(955,000,000)	(1,531,000,000)
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)					4,000,000	0
Net Investment Hedges
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance		236,000,000		(169,000,000)	236,000,000	(169,000,000)
Other comprehensive income (loss) before reclassifications					(1,276,000,000)	152,000,000
Reclassifications					0	0
Other comprehensive (loss) income					(1,276,000,000)	152,000,000
Ending balance	(1,040,000,000)		(17,000,000)		(1,040,000,000)	(17,000,000)
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)					0	0
Net Change in Retirement Obligations
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance		(1,852,000,000)		(1,308,000,000)	(1,852,000,000)	(1,308,000,000)
Other comprehensive income (loss) before reclassifications					(14,000,000)	(1,000,000)
Reclassifications					34,000,000	26,000,000
Other comprehensive (loss) income					20,000,000	25,000,000
Ending balance	(1,832,000,000)		(1,283,000,000)		(1,832,000,000)	(1,283,000,000)
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)					(5,000,000)	0
Reclassifications, tax expense (benefit)					(8,000,000)	(6,000,000)
Unrealized Gain (Loss) on Cash Flow Hedges
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance		$ 266,000,000		$ 194,000,000	266,000,000	194,000,000
Other comprehensive income (loss) before reclassifications					(359,000,000)	82,000,000
Reclassifications					(36,000,000)	(84,000,000)
Other comprehensive (loss) income					(395,000,000)	(2,000,000)
Ending balance	$ (129,000,000)		$ 192,000,000		(129,000,000)	192,000,000
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)					(93,000,000)	21,000,000
Reclassifications, tax expense (benefit)					$ (10,000,000)	$ (26,000,000)