5. INVENTORIES (Details Narrative) - USD ($)	3 Months Ended	9 Months Ended
Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2018	Jan. 31, 2017
Cost of contract manufacturing	$ 10,951,000	$ 7,974,000	$ 47,641,000	$ 26,477,000
Idle Capacity Costs [Member]
Cost of contract manufacturing	$ 5,344,000		$ 11,182,000

Costs incurred in production of other products during the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration