Leases - Summary of Future Lease Payments for Operating and Finance Leases (Detail) - USD ($) $ in Thousands	Jan. 31, 2021	Apr. 30, 2020
Operating and Finance Lease liabilities payments
2021	$ 1,174
2022	4,602
2023	4,625
2024	4,670
2025	3,506
Thereafter	49,495
Total future lease payments	68,072
Less amounts representing interest	(22,669)
Present value of lease payments	45,403
Less current maturities of lease liabilities	(2,392)
Long-term maturities of lease liabilities	43,011
Operating Leases
2021	413
2022	1,546
2023	1,554
2024	1,545
2025	326
Thereafter	712
Total future lease payments	6,096
Less amounts representing interest	(826)
Total operating lease liabilities	5,270
Less current maturities of lease liabilities	(1,319)	$ (1,506)
Long-term maturities of lease liabilities	3,951
Financing Leases
2021	761
2022	3,056
2023	3,071
2024	3,125
2025	3,180
Thereafter	48,783
Total future lease payments	61,976
Less amounts representing interest	(21,843)
Total finance lease liabilities	40,133
Less current maturities of lease liabilities	(1,073)	(1,046)
Long-term maturities of lease liabilities	$ 39,060	$ 39,873

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Lessee operating and finance lease liability payments due after year four.

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Lessee operating and finance lease liability payments due year four.

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Lessee operating and finance lease liability payments due year three.

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Lessee operating and finance lease liability payments due year two.

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Lessee operating and finance lease liability payments remainder of fiscal year.

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Present value of lessee's discounted obligation for lease payments from finance lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-SubTopic 20
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-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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