The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=96864182&loc=d3e11374-113907

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Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

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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

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
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Recent Accounting Pronouncements - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Jan. 27, 2018	Jan. 27, 2018	Jan. 28, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in accounting principle, effect of adoption		$ 2,347
Additional Paid-In Capital
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in accounting principle, effect of adoption		1,310
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in accounting principle, effect of adoption		1,037
ASU 2016-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Excess tax benefits on share based payments	$ 11	915
Unrecognized excess tax benefits	$ 1,823	1,823
Excess tax benefit from share-based compensation, operating activities			$ 88
ASU 2016-09 \| Scenario, Previously Reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Excess tax benefit from share-based compensation, financing activities			$ 88
ASU 2016-09 \| Additional Paid-In Capital
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in accounting principle, effect of adoption		1,310
ASU 2016-09 \| Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in accounting principle, effect of adoption		(786)
ASU 2016-09 \| Deferred Taxes
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in accounting principle, effect of adoption		$ (524)