Derivative Financial Instruments - Fair Value of Derivative Instruments Included in Condensed Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Jan. 27, 2018	Apr. 29, 2017
Derivatives, Fair Value [Line Items]
Interest rate contracts, assets, fair value	$ 1,061	$ 1,188
Interest rate contracts, liabilities, fair value	1,061	1,188
Other Noncurrent Assets \| Interest Rate Contracts
Derivatives, Fair Value [Line Items]
Interest rate contracts, assets, fair value	1,061	1,188
Other Noncurrent Liabilities \| Interest Rate Contracts
Derivatives, Fair Value [Line Items]
Interest rate contracts, liabilities, fair value	$ 1,061	$ 1,188

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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