Note 11 - Lease Right-to-use - Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Oct. 31, 2020	Apr. 30, 2020
2022	$ 5,244
2023	5,260
2024	5,314
2025	5,317
2026	5,268
Thereafter	56,979
Total minimum lease payments	83,382
Less amount representing interest	40,567
Present value of net minimum lease payments	42,815
Less current maturities of lease liability	1,228	$ 1,163
Lease liability, net of current maturities	$ 41,587	$ 42,211

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

+ References

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Amount of lessee's undiscounted obligation for lease payments for finance lease.

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- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease, due after fifth fiscal year following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due after fifth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in fourth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

+ References

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in third rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in second rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

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