2. Summary of Significant Accounting Policies (Details - Property and Equipment) - USD ($) $ in Thousands	Oct. 31, 2019	Apr. 30, 2019
Property and equipment, gross	$ 43,007	$ 40,194
Less: Accumulated depreciation and amortization	(16,017)	(14,569)
Total property and equipment, net	26,990	25,625
Leasehold Improvements [Member]
Property and equipment, gross	21,132	20,574
Laboratory and manufacturing equipment [Member]
Property and equipment, gross	13,137	12,858
Computer Equipment and software [Member]
Property and equipment, gross	4,719	4,644
Furniture, fixtures and office equipment [Member]
Property and equipment, gross	685	528
Construction in Progress [Member]
Property and equipment, gross	$ 3,334	$ 1,590

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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