Stockholders' Equity - Summary of Activities Related to Stock Repurchase Program (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended	195 Months Ended
Jul. 26, 2019	Jul. 27, 2018	Jul. 26, 2019
Equity [Abstract]
Number of shares repurchased	4		317
Average price per share	$ 64.87		$ 37.80
Aggregate purchase price	$ 250	$ 500
Remaining authorization at end of period	$ 1,639		$ 1,639

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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