2. Summary of Significant Accounting Policies (Details - Property and Equipment) - USD ($) $ in Thousands	Apr. 30, 2019	Apr. 30, 2018
Property and equipment, gross	$ 40,194	$ 38,851
Less: Accumulated depreciation and amortization	(14,569)	(12,372)
Total property and equipment, net	25,625	26,479
Leasehold Improvements [Member]
Property and equipment, gross	20,574	20,686
Laboratory and manufacturing equipment [Member]
Property and equipment, gross	12,858	10,258
Computer Equipment and software [Member]
Property and equipment, gross	4,644	4,087
Furniture, fixtures and office equipment [Member]
Property and equipment, gross	528	510
Construction in Progress [Member]
Property and equipment, gross	$ 1,590	$ 3,310

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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