Note 1 - Significant Accounting Policies (Details Textual) - USD ($) $ in Millions	Jan. 27, 2018	Apr. 29, 2017
Inventory, Finished Goods, Gross	$ 37.2	$ 35.0
Inventory, Raw Materials, Gross	$ 23.6	$ 18.4

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_InventoryFinishedGoods
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant