Schedule II - Valuation and Qualifying Accounts and Reserves (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Apr. 28, 2013	Apr. 29, 2012	Apr. 27, 2011
Allowance for Trade Receivables [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation Reserves, Balance at beginning of period	$ 10,680	$ 10,909	$ 10,196
Charged to costs and expenses	1,937	4,220	1,997
Deductions	4,484	3,807	2,053
Exchange	(176)	(642)	769
Valuation Reserves, Balance at end of period	7,957	10,680	10,909
Allowance For Other Receivables [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation Reserves, Balance at beginning of period	607	503	268
Charged to costs and expenses	(183)	108	203
Deductions	64	8	0
Exchange	0	4	32
Valuation Reserves, Balance at end of period	$ 360	$ 607	$ 503

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Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24092-122690

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- Definition

+ References

+ Details

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- Definition

+ References

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- Definition

Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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+ Details

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