Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28555-108399

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

Long-Term Debt - Summary of Long-Term Debt (Parenthetical) (Detail) - USD ($) $ in Millions	Oct. 31, 2020	Apr. 29, 2020	Jan. 31, 2020	Oct. 31, 2019	Oct. 18, 2019	Mar. 29, 2019	Jul. 18, 2018	Apr. 25, 2017
Debt Instrument [Line Items]
Debt issuance costs		$ 0.2	$ 0.4		$ 0.2
Term Loan [Member]
Debt Instrument [Line Items]
Debt issuance costs	$ 1.7			$ 2.2		$ 0.8	$ 0.6	$ 2.0