Leases - Additional Information (Detail)	3 Months Ended
Jul. 31, 2021 USD ($)
Lessee Lease Description [Line Items]
Operating lease cost	$ 371,000
Short-term operating lease costs	33,000
Financing lease Amortization	525,000
Financing lease interest expense	$ 497,000
Operating leases, weighted average lease term	3 years 10 months 24 days
Operating leases, weighted average discount rate	4.50%
Financing leases, weighted average lease term	17 years 2 months 12 days
Financing leases, weighted average discount rate	5.00%
Cash paid for amounts included in measurement of liabilities and operating cash flows	$ 1,100,000
National Logistics Facility
Lessee Lease Description [Line Items]
Percentage of sublease	59.00%
National Logistics Facility \| Other Income/(Expense)
Lessee Lease Description [Line Items]
Income related to sublease agreement	$ 501,000

Percentage of sublease.

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- Definition

short-term operating lease costs.

+ References

No definition available.

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- Definition

Amount of interest expense on finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

+ References

+ Details

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- Definition

Weighted average discount rate for finance lease calculated at point in time.

+ References

+ Details

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- Definition

Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=121568110&loc=SL77918982-209971

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of sublease income excluding finance and operating lease expense.

+ References

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