INCOME TAXES (Deferred Tax Assets) (Details) (USD $) In Thousands, unless otherwise specified	Feb. 28, 2013	Feb. 29, 2012
INCOME TAXES [Abstract]
Net operating loss carryforwards	$ 22,977	$ 28,214
Depreciation, amortization and impairments	9,585	11,123
Research and development credits	6,089	5,344
Stock-based compensation	1,990	2,122
Capital loss carryforward	831	848
Other tax credits	636	1,028
Inventory reserve	534	761
Warranty reserve	515	393
Payroll and employee benefit accruals	469	408
Allowance for doubtful accounts	179	101
Other, net	1,170	549
Gross deferred tax assets	44,975	50,891
Valuation allowance	(3,959)	(39,054)
Net deferred tax assets	41,016	11,837
Less current portion	6,400	5,425
Non-current portion	$ 34,616	$ 6,412