5. PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Thousands	Jan. 31, 2019	Apr. 30, 2018
Property, Plant and Equipment [Abstract]
Leasehold improvements	$ 20,648	$ 20,686
Laboratory and manufacturing equipment	12,427	10,258
Furniture, fixtures, office equipment and software	5,210	4,597
Construction-in-progress	1,656	3,310
Total property and equipment	39,941	38,851
Less accumulated depreciation and amortization	(14,065)	(12,372)
Total property and equipment, net	$ 25,876	$ 26,479

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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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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- Definition

Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount before accumulated depreciation, depletion and amortization of other physical assets used in the normal conduct of business to produce goods and services and not intended for resale.

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