Derivative Financial Instruments - Fair Value of Interest Rate Contracts Included in Condensed Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Jan. 28, 2017	Apr. 30, 2016
Derivatives, Fair Value [Line Items]
Interest rate contracts, assets, fair value	$ 2,069	$ 816
Interest rate contracts, liabilities, fair value	2,069	816
Other Noncurrent Assets [Member] \| Interest Rate Contracts [Member]
Derivatives, Fair Value [Line Items]
Interest rate contracts, assets, fair value	2,069	816
Other Noncurrent Liabilities [Member] \| Interest Rate Contracts [Member]
Derivatives, Fair Value [Line Items]
Interest rate contracts, liabilities, fair value	$ 2,069	$ 816

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No definition available.

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

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- Definition

Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

+ References

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