Stockholders' Equity - Summary of Activities Related to Stock Repurchase Program (Detail) $ / shares in Units, shares in Millions, $ in Millions	9 Months Ended	153 Months Ended
Jan. 29, 2016 USD ($) $ / shares shares	Jan. 29, 2016 USD ($) $ / shares shares
Equity [Abstract]
Number of shares repurchased \| shares	23	237
Average price per share \| $ / shares	$ 30.75	$ 33.22
Aggregate purchase price	$ 698
Remaining authorization at end of period	$ 1,762	$ 1,762

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

+ Details

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- Definition

Number of shares that have been repurchased and retired during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

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- Definition

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).

+ References

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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