Note 11 - Finance Lease Right-of-use - Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Jan. 31, 2020	Apr. 30, 2019
2021	$ 5,223
2022	5,243
2023	5,273
2024	5,328
2025	5,292
Thereafter	60,937
Total minimum lease payments	87,296
Less amount representing interest	43,652
Present value of net minimum lease payments	43,644
Less current maturities of finance lease liability	1,123	$ 8
Finance lease liability, net of current maturities	$ 42,521	$ 1,689

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=77888426&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=77888419&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=77888419&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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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=77888426&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.

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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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