Stockholders' Equity - Accumulated Other Comprehensive Income (Loss) by Component Net of Tax (Detail) - USD ($) $ in Millions	12 Months Ended
	Apr. 28, 2017	Apr. 29, 2016	Apr. 24, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balances	$ 2,881	$ 3,414	$ 3,787
OCI before reclassifications, net of tax	8	(9)
Amounts reclassified from AOCI, net of tax	(6)	2
Other comprehensive income (loss):	2	(7)	(33)
Balances	2,780	2,881	3,414
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balances	(19)	(23)
OCI before reclassifications, net of tax	(10)	4
Amounts reclassified from AOCI, net of tax	0	0
Other comprehensive income (loss):	(10)	4
Balances	(29)	(19)	(23)
Defined Benefit Obligation Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balances	(16)	(13)
OCI before reclassifications, net of tax	16	(5)
Amounts reclassified from AOCI, net of tax	0	2
Other comprehensive income (loss):	16	(3)
Balances	0	(16)	(13)
Unrealized Gains (Losses) on Available-for-Sale Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balances	6	11
OCI before reclassifications, net of tax	(6)	(4)
Amounts reclassified from AOCI, net of tax	0	(1)
Other comprehensive income (loss):	(6)	(5)
Balances	0	6	11
Unrealized Gains (Losses) on Derivative Instruments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balances	(2)	1
OCI before reclassifications, net of tax	8	(4)
Amounts reclassified from AOCI, net of tax	(6)	1
Other comprehensive income (loss):	2	(3)
Balances	0	(2)	1
AOCI Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balances	(31)	(24)	9
Balances	$ (29)	$ (31)	$ (24)