2. Summary of Significant Accounting Policies (Details - Receivables) - USD ($) $ in Thousands	Apr. 30, 2019	Apr. 30, 2018
Accounting Policies [Abstract]
Trade receivables	$ 7,374	$ 3,539
Other receivables	0	215
Trade and other receivables	$ 7,374	$ 3,754

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant