Summary of Impact of Adoption of New Accounting Pronouncements on Statement of Earnings (Detail) - USD ($) $ in Thousands	3 Months Ended
Jul. 28, 2018	Jul. 29, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Sales	$ 794,776	$ 853,316
Cost of sales	566,704	599,835
Gross profit	228,072	$ 253,481
Calculated under Revenue Guidance in Effect before Topic 606 \| ASU 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Sales	795,182
Cost of sales	566,704
Gross profit	228,478
Difference between Revenue Guidance in Effect before and after Topic 606 \| ASU 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Sales	(406)
Gross profit	$ (406)

The aggregate of buying and occupancy costs reported during the period related to merchandise sold. Costs could include, but not be limited to, inbound and outbound freight; costs of operating distribution centers; payroll, benefits, and travel costs directly associated with buying inventory; systems costs related to the buying and tracking of inventory; rent; depreciation; property taxes; and facility operations.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1,2)
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+ References

No definition available.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8933-108599

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

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