Note 3 - Components of Equipment and Leasehold Improvements (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Mar. 31, 2015
Equipment [Member]
Equipment and leasehold improvements, gross	$ 10,009	$ 9,782
Leasehold Improvements [Member]
Equipment and leasehold improvements, gross	10,232	10,216
Furniture and Fixtures [Member]
Equipment and leasehold improvements, gross	298	298
Equipment and leasehold improvements, gross	20,539	20,296
Less accumulated depreciation and amortization	(12,862)	(12,549)
Construction-in-progress	7,856	7,007
Equipment and leasehold improvements, net	$ 15,533	$ 14,754

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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