Accumulated Other Comprehensive Income and Supplemental Equity Disclosure - Supplemental Equity Schedule (Details) - USD ($) $ in Millions	3 Months Ended
	Jul. 27, 2018	Jul. 28, 2017	Apr. 27, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	$ 50,822	$ 50,416
Net income (loss)	1,077	1,009
Other comprehensive income (loss)	(584)	689
Dividends to shareholders	(677)	(625)
Issuance of shares under stock purchase and award plans	446	138
Repurchase of ordinary shares	(820)	(1,228)
Stock-based compensation	64	92
Changes to noncontrolling ownership interests	1
Cumulative effect of change in accounting principle			$ 296
Balance	50,329	50,787
Total Shareholders' Equity
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	50,720	50,294
Net income (loss)	1,075	1,016
Other comprehensive income (loss)	(584)	689
Dividends to shareholders	(677)	(625)
Issuance of shares under stock purchase and award plans	446	138
Repurchase of ordinary shares	(820)	(1,228)
Stock-based compensation	64	92
Cumulative effect of change in accounting principle			$ 296
Balance	50,224	50,672
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	102	122
Net income (loss)	2	(7)
Changes to noncontrolling ownership interests	1
Balance	$ 105	$ 115