Dividends - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Apr. 30, 2016	May 02, 2015	May 03, 2014
Dividends Payable [Line Items]
Cash dividends paid to preferred shareholders	$ 3,941	$ 16,026	$ 15,768
Cash dividends paid to common stockholders	$ 46,056	$ 0

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.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
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- Definition

Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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- Definition

Amount of cash outflow in the form of ordinary dividends to preferred shareholders of the parent entity.

+ References

+ Details

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