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Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 280

-SubTopic 10

-Section 50

-Paragraph 41

-Subparagraph (b)

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Article 5

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Segment Disclosure - Net Sales and Long-lived Assets by Geographic Area (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Jan. 31, 2015	Jan. 25, 2014	Jan. 31, 2015	Jan. 25, 2014	Apr. 26, 2014
Net sales:
Net sales	$ 118,123us-gaap_SalesRevenueNet	$ 115,369us-gaap_SalesRevenueNet	$ 457,856us-gaap_SalesRevenueNet	$ 415,730us-gaap_SalesRevenueNet
Long-lived assets:
Long-lived assets	69,963us-gaap_NoncurrentAssets		69,963us-gaap_NoncurrentAssets		65,270us-gaap_NoncurrentAssets
United States
Net sales:
Sales	90,127	94,454	370,168	343,536
Long-lived assets:
Long-lived assets	65,215		65,215		60,846
Outside U.S.
Net sales:
Sales	27,996	20,915	87,688	72,194
Long-lived assets:
Long-lived assets	$ 4,748		$ 4,748		$ 4,424