4. Leases (Details - Operating leases assets and liabilities) - USD ($) $ in Thousands	Apr. 30, 2021	Apr. 30, 2020
Lessee Disclosure [Abstract]
Operating lease right-of-use assets	$ 18,691	$ 20,100
Operating lease liabilities	1,355	1,228
Operating lease liabilities, less current portion	19,889	21,244
Total operating lease liabilities	$ 21,244	$ 22,472
Weighted average lease term	9 years 7 months 6 days	10 years 6 months
Weighted average discount rate	8.00%	8.00%

No definition available.

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- Definition

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

+ 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=123391704&loc=SL77918627-209977

+ Details

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ 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 (a)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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- Definition

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

+ 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 (g)(4)
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918686-209980

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=123414884&loc=SL77918982-209971

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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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=123414884&loc=SL77918982-209971

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Subparagraph (g)(3)
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918686-209980

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