Derivative Financial Instruments - Fair Value of Derivative Instruments Included in Condensed Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Jan. 26, 2019	Apr. 28, 2018
Derivatives, Fair Value [Line Items]
Interest rate contracts, assets, fair value	$ 1,169	$ 1,613
Interest rate contracts, liabilities, fair value	1,453	1,613
Other Noncurrent Assets \| Interest rate contracts
Derivatives, Fair Value [Line Items]
Interest rate contracts, assets, fair value	1,169	1,613
Other Accrued Liabilities \| Interest rate contracts
Derivatives, Fair Value [Line Items]
Interest rate contracts, liabilities, fair value	28	0
Other Noncurrent Liabilities \| Interest rate contracts
Derivatives, Fair Value [Line Items]
Interest rate contracts, liabilities, fair value	$ 1,425	$ 1,613

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.

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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=77997519&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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