Allowance for Doubtful Accounts - Summary of the Activity in the Allowance for Doubtful Accounts (Detail) - Allowance for doubtful accounts [Member] - USD ($)	3 Months Ended
Jul. 31, 2022	Aug. 01, 2021
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	$ 292,000	$ 591,000
Provision for bad debts	57,000	(11,000)
Ending balance	$ 349,000	$ 580,000

Amount of valuation and qualifying accounts and reserves.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09(Column B))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09(Column E))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690

Name:	us-gaap_ValuationAllowancesAndReservesBalance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant