Accumulated Other Comprehensive Loss - Changes in AOCI (Details) - USD ($)		3 Months Ended				6 Months Ended
		Oct. 25, 2019	Jul. 26, 2019	Oct. 26, 2018	Jul. 27, 2018	Oct. 25, 2019	Oct. 26, 2018	Apr. 27, 2019	[1]	Apr. 28, 2018
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance		$ 50,497,000,000	$ 50,212,000,000	$ 50,329,000,000	$ 50,822,000,000	$ 50,212,000,000	$ 50,822,000,000
Other comprehensive (loss) income		(127,000,000)	227,000,000	(292,000,000)	(584,000,000)	100,000,000	(876,000,000)
Cumulative effect of change in accounting principle								$ (33,000,000)		$ 0	[2]
Ending balance		50,719,000,000	50,497,000,000	49,714,000,000	50,329,000,000	50,719,000,000	49,714,000,000
Unrealized (Loss) Gain on Investment Securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance			(45,000,000)		(194,000,000)	(45,000,000)	(194,000,000)
Other comprehensive (loss) income before reclassifications						68,000,000	(19,000,000)
Reclassifications						5,000,000	10,000,000
Other comprehensive (loss) income						73,000,000	(9,000,000)
Cumulative effect of change in accounting principle										47,000,000
Ending balance		28,000,000		(156,000,000)		28,000,000	(156,000,000)
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)						1,000,000	(1,000,000)
Reclassifications, tax expense (benefit)						(2,000,000)	0
Cumulative Translation Adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance			(1,383,000,000)		(11,000,000)	(1,383,000,000)	(11,000,000)
Other comprehensive (loss) income before reclassifications						(148,000,000)	(1,252,000,000)
Reclassifications						0	0
Other comprehensive (loss) income						(148,000,000)	(1,252,000,000)
Cumulative effect of change in accounting principle										0
Ending balance		(1,531,000,000)		(1,263,000,000)		(1,531,000,000)	(1,263,000,000)
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)						0	(5,000,000)
Net Investment Hedges
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance			(169,000,000)			(169,000,000)
Other comprehensive (loss) income before reclassifications						152,000,000
Reclassifications						0
Other comprehensive (loss) income						152,000,000
Ending balance		(17,000,000)				(17,000,000)
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)						0
Net Investment Hedges
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance					(257,000,000)		(257,000,000)
Other comprehensive (loss) income before reclassifications							0
Reclassifications							0
Other comprehensive (loss) income							0
Cumulative effect of change in accounting principle										0
Ending balance				(257,000,000)			(257,000,000)
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)							0
Net Change in Retirement Obligations
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance			(1,308,000,000)		(1,117,000,000)	(1,308,000,000)	(1,117,000,000)
Other comprehensive (loss) income before reclassifications						(1,000,000)	0
Reclassifications						26,000,000	48,000,000
Other comprehensive (loss) income						25,000,000	48,000,000
Cumulative effect of change in accounting principle										0
Ending balance		(1,283,000,000)		(1,069,000,000)		(1,283,000,000)	(1,069,000,000)
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)						0	0
Reclassifications, tax expense (benefit)						(6,000,000)	(10,000,000)
Unrealized Gain (Loss) on Cash Flow Hedges
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance			194,000,000			194,000,000
Other comprehensive (loss) income before reclassifications						82,000,000
Reclassifications						(84,000,000)
Other comprehensive (loss) income						(2,000,000)
Ending balance		192,000,000				192,000,000
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)						21,000,000
Reclassifications, tax expense (benefit)						(26,000,000)
Unrealized (Loss) Gain on Cash Flow Hedges
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance					(207,000,000)		(207,000,000)
Other comprehensive (loss) income before reclassifications							343,000,000
Reclassifications							(3,000,000)
Other comprehensive (loss) income							340,000,000
Cumulative effect of change in accounting principle										0
Ending balance				133,000,000			133,000,000
Other Comprehensive Income (Loss), Tax [Abstract]
Other comprehensive income (loss) before reclassifications, tax expense (benefit)							100,000,000
Reclassifications, tax expense (benefit)							(3,000,000)
Total Accumulated Other Comprehensive (Loss) Income
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance		(2,484,000,000)	(2,711,000,000)	(2,323,000,000)	(1,786,000,000)	(2,711,000,000)	(1,786,000,000)
Other comprehensive (loss) income before reclassifications						153,000,000	(928,000,000)
Reclassifications						(53,000,000)	55,000,000
Other comprehensive (loss) income		(127,000,000)	227,000,000	(289,000,000)	(584,000,000)	100,000,000	(873,000,000)
Cumulative effect of change in accounting principle	[2]									47,000,000
Ending balance		(2,611,000,000)	(2,484,000,000)	(2,612,000,000)	(2,323,000,000)	(2,611,000,000)	(2,612,000,000)
Retained Earnings
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance		26,377,000,000	26,270,000,000	24,730,000,000	24,379,000,000	26,270,000,000	24,379,000,000
Cumulative effect of change in accounting principle								$ (33,000,000)		$ (47,000,000)	[2]
Ending balance		$ 27,018,000,000	$ 26,377,000,000	$ 25,171,000,000	$ 24,730,000,000	$ 27,018,000,000	$ 25,171,000,000

[1] See Note 2 to the consolidated financial statements for discussion regarding the adoption of accounting standards during the first quarter fiscal year 2020.

[2] The cumulative effect of change in accounting principle during the first quarter of fiscal year 2019 resulted from the adoption of accounting guidance that requires equity investments (except those accounted for under the equity method of accounting or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income. As a result of the adoption, the Company reclassified $47 million from accumulated other comprehensive loss to the opening balance of retained earnings as of April 28, 2018.