Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jan. 27, 2017	Jan. 29, 2016	Jan. 27, 2017	Jan. 29, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 820	$ 1,095	$ 2,860	$ 2,435
Other comprehensive loss, net of tax:
Unrealized (loss) gain on available-for-sale securities, net of tax (benefit) expense of $(40), $(34), $(3), and $(149) respectively	(115)	(61)	(40)	(268)
Currency adjustment, net	(553)	(1,454)	(1,239)	(1,513)
Net change in retirement obligations, net of tax expense of $5, $10, $15, and $30, respectively	22	27	66	62
Unrealized gain (loss) on derivatives, net of tax expense (benefit) of $55, $(3), 113 and $(36), respectively	95	(6)	202	(62)
Other comprehensive loss	(551)	(1,494)	(1,011)	(1,781)
Comprehensive income (loss) including noncontrolling interests	269	(399)	1,849	654
Comprehensive loss attributable to noncontrolling interests	(1)	0	(5)	0
Comprehensive income (loss) attributable to Medtronic	$ 270	$ (399)	$ 1,854	$ 654