Revenue - Narrative (Details) - USD ($) $ in Millions	6 Months Ended
Oct. 26, 2018	Apr. 27, 2018
Disaggregation of Revenue [Line Items]
Deferred revenue	$ 280	$ 289
Revenue recognized that was previously included in deferred revenue	126
Estimated revenue expected to be recognized in future periods related to unsatisfied performance obligations	$ 600
Period over which remaining performance obligations are expected to be recognized as revenue	3 years
Other accrued expenses
Disaggregation of Revenue [Line Items]
Rebate obligations	$ 697	614
Deferred revenue	186	196
Reduction of accounts receivable
Disaggregation of Revenue [Line Items]
Rebate obligations	410	376
Other liabilities
Disaggregation of Revenue [Line Items]
Deferred revenue	$ 94	$ 93

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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