Share Based Payments Summary of Stock Options Outstanding and Activity (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	6 Months Ended
	Aug. 31, 2014
Options
Outstanding, beginning of period	6,984,605
Granted	561,219
Exercised	617,706	[1]
Forfeited	25,000
Expired	986,610
Outstanding, end of period	5,916,508
Exercisable, end of period	2,649,017
Price
Outstanding, beginning of period	$ 3.74
Granted	$ 2.91
Exercised	$ 0.54	[1]
Forfeited	$ 0.70
Expired or exchanged	$ 17.45
Outstanding, end of period	$ 1.72
Exercisable, end of period	$ 1.87
Outstanding	7 years 1 month 15 days
Exercisable, end of period	5 years 7 months
Outstanding, end of period	$ 7,180
Exercisable, end of period	$ 3,666

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