Note 9 - Pension Plans (Details) - Contributions for All Multi-employer Pension Plans (USD $) In Thousands, unless otherwise specified	12 Months Ended
May 03, 2014	Apr. 27, 2013	Apr. 28, 2012
Multiemployer Plans [Line Items]
Contribution	$ 1,850	$ 1,784	$ 1,643
CSSS Fund [Member]
Multiemployer Plans [Line Items]
Contribution	1,079	1,051	944
WCT Fund [Member]
Multiemployer Plans [Line Items]
Contribution	476	471	455
Other Multi-Employer Pension Funds [Member]
Multiemployer Plans [Line Items]
Contribution	$ 295	$ 262	$ 244

Amount of contributions made to multiemployer plans by the employer. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=35742057&loc=SL14450702-114947

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=35742057&loc=SL14450691-114947

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 5

-Subparagraph (e)(1)

-URI http://asc.fasb.org/extlink&oid=35742057&loc=SL14450657-114947

Name:	us-gaap_MultiemployerPlanPeriodContributions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration