Accumulated Other Comprehensive Loss - Changes in AOCI (Details) - USD ($)	3 Months Ended
	Jul. 31, 2020	Jul. 26, 2019
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 50,872,000,000	$ 50,212,000,000
Other comprehensive (loss) income	(217,000,000)	227,000,000
Ending balance	50,443,000,000	50,497,000,000
Total Accumulated Other Comprehensive (Loss) Income
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(3,560,000,000)	(2,711,000,000)
Other comprehensive income (loss) before reclassifications	(196,000,000)	242,000,000
Reclassifications	(26,000,000)	(15,000,000)
Other comprehensive (loss) income	(222,000,000)	227,000,000
Ending balance	(3,782,000,000)	(2,484,000,000)
Unrealized (Loss) Gain on Investment Securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	0	(45,000,000)
Other comprehensive income (loss) before reclassifications	125,000,000	51,000,000
Reclassifications	0	5,000,000
Other comprehensive (loss) income	125,000,000	56,000,000
Ending balance	125,000,000	11,000,000
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)	30,000,000	(1,000,000)
Reclassifications, tax expense (benefit)	0	(1,000,000)
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)
Other comprehensive income (loss) before reclassifications	1,112,000,000	66,000,000
Reclassifications	0	0
Other comprehensive (loss) income	1,112,000,000	66,000,000
Ending balance	(1,098,000,000)	(1,317,000,000)
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)
Other comprehensive income (loss) before reclassifications	(1,112,000,000)	99,000,000
Reclassifications	0	0
Other comprehensive (loss) income	(1,112,000,000)	99,000,000
Ending balance	(876,000,000)	(70,000,000)
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)
Other comprehensive income (loss) before reclassifications	(12,000,000)	0
Reclassifications	15,000,000	13,000,000
Other comprehensive (loss) income	3,000,000	13,000,000
Ending balance	(1,849,000,000)	(1,295,000,000)
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)	(5,000,000)	0
Reclassifications, tax expense (benefit)	(4,000,000)	(3,000,000)
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
Other comprehensive income (loss) before reclassifications	(309,000,000)	26,000,000
Reclassifications	(41,000,000)	(33,000,000)
Other comprehensive (loss) income	(350,000,000)	(7,000,000)
Ending balance	(84,000,000)	187,000,000
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)	(80,000,000)	1,000,000
Reclassifications, tax expense (benefit)	$ (11,000,000)	$ (11,000,000)