Stockholders' Equity - Activity Related to Stock Options (Detail) - $ / shares shares in Millions	12 Months Ended
Apr. 26, 2019	Apr. 27, 2018	Apr. 28, 2017
Number of Shares
Beginning balance, Number of Shares	1	4	9
Options exercised, Number of Shares	(1)	(2)	(3)
Options forfeited and expired, Number of Shares	0	(1)	(2)
Ending balance, Number of Shares	0	1	4
Options Exercisable, Number of Shares	0
Weighted-Average Exercise Price
Beginning balance, Weighted-Average Exercise Price	$ 31.19	$ 35.76	$ 34.01
Options exercised, Weighted-Average Exercise Price	$ 32.50	36.99	25.61
Options forfeited and expired, Weighted-Average Exercise Price		40.50	39.36
Ending balance, Weighted-Average Exercise Price		$ 31.19	$ 35.76

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.

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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.

+ References

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Weighted average price of options that were either forfeited or expired.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

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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No definition available.

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- Definition

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

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- Definition

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

+ References

No definition available.

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- Definition

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

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