Stockholders' Equity - Activity Related to Stock Options (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Apr. 27, 2018	Apr. 28, 2017	Apr. 29, 2016
Number of Shares
Beginning balance, Number of Shares	4	9	12
Options assumed in acquisition, Number of Shares			2
Options exercised, Number of Shares	(2)	(3)	(2)
Options forfeited and expired, Number of Shares	(1)	(2)	(3)
Ending balance, Number of Shares	1	4	9
Options Exercisable, Number of Shares	1
Weighted-Average Exercise Price
Beginning balance, Weighted-Average Exercise Price	$ 35.76	$ 34.01	$ 37.74
Options assumed in acquisition, Weighted-Average Exercise Price			5.20
Options exercised, Weighted-Average Exercise Price	36.99	25.61	19.64
Options forfeited and expired, Weighted-Average Exercise Price	40.50	39.36	38.27
Ending balance, Weighted-Average Exercise Price	31.19	$ 35.76	$ 34.01
Options Exercisable, Weighted-Average Exercise Price	$ 34.30
Weighted-Average Remaining Contractual Term and Aggregate Intrinsic Value
Outstanding, Weighted-Average Remaining Contractual Term	3 years 5 months 23 days
Exercisable, Weighted-Average Remaining Contractual Term	2 years 10 months 28 days
Outstanding, Aggregate Intrinsic Value	$ 44
Exercisable, Aggregate Intrinsic Value	$ 34

Gross number of share options assumed in acquisition during the period.

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Share based compensation arrangements by share based payment award options assumed in acquisition in period weighted average exercise price.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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-Subparagraph (c)(1)(iv)(3)-(4)
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Weighted average price of options that were either forfeited or expired.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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