Note 11 - Pension Plans - Contributions for All Multi-employer Pension Plans (Details) - USD ($) $ in Millions	12 Months Ended
Apr. 27, 2024	Apr. 29, 2023	Apr. 30, 2022
Fund	$ 2.6	$ 2.6	$ 2.5
CSSS Fund [Member]
Fund	1.6	1.6	1.5
WCT Fund [Member]
Fund	0.8	0.8	0.8
Other Multi-employer Pension Funds [Member]
Fund	$ 0.2	$ 0.2	$ 0.2

Amount of cost for employer contribution to multiemployer plan. Multiemployer plan includes, but is not limited to, pension plan determined to be individually significant and insignificant and other postretirement benefit plan.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 55
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480547/715-80-55-8

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 35
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480606/715-80-35-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480576/715-80-50-11

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480576/715-80-50-9

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