Retirement Benefit Plans , Net Periodic Cost and AOCI (Details) - USD ($) $ in Millions	12 Months Ended
	Apr. 28, 2017	Apr. 29, 2016	Apr. 24, 2015
Net Periodic Benefit Cost
Special termination benefits	$ 73
U.S. Pension Benefits | Pension benefits
Net Periodic Benefit Cost
Service cost	117	$ 120	$ 104
Interest cost	109	122	105
Expected return on plan assets	(195)	(180)	(160)
Amortization of prior service cost	1	0	0
Amortization of net actuarial loss	88	98	65
Settlement gain	0	(1)	0
Special termination benefits	60	0	0
Net periodic benefit cost	180	159	114
Amounts Recognized in AOCI
Net actuarial (gain) loss	(61)
Amortization of prior service cost	(1)
Amortization of net actuarial loss	(88)
Prior service cost	0
Effect of exchange rates	0
Total (gain) loss recognized in accumulated other comprehensive loss	(150)
Total loss recognized in net periodic benefit cost and accumulated other comprehensive loss	30
Non-U.S. Pension Benefits | Pension benefits
Net Periodic Benefit Cost
Service cost	70	81	60
Interest cost	26	31	33
Expected return on plan assets	(48)	(48)	(41)
Amortization of prior service cost	(1)	0	0
Amortization of net actuarial loss	17	20	12
Settlement gain	0	(10)	0
Special termination benefits	0	0	0
Net periodic benefit cost	64	$ 74	$ 64
Amounts Recognized in AOCI
Net actuarial (gain) loss	121
Amortization of prior service cost	1
Amortization of net actuarial loss	(17)
Prior service cost	8
Effect of exchange rates	(13)
Total (gain) loss recognized in accumulated other comprehensive loss	100
Total loss recognized in net periodic benefit cost and accumulated other comprehensive loss	$ 164