Balance Sheet Details - Deferred Revenue and Financed Unearned Services Revenue (Detail) - USD ($) $ in Millions	Oct. 27, 2017	Apr. 28, 2017
Deferred Revenue And Credits [Line Items]
Deferred revenue and financed unearned services revenue	$ 3,167	$ 3,342
Short-term	1,645	1,744
Long-term	1,522	1,598
Deferred product revenue
Deferred Revenue And Credits [Line Items]
Deferred revenue and financed unearned services revenue	123	124
Deferred services revenue
Deferred Revenue And Credits [Line Items]
Deferred revenue and financed unearned services revenue	2,881	2,999
Financed unearned services revenue
Deferred Revenue And Credits [Line Items]
Deferred revenue and financed unearned services revenue	$ 163	$ 219