Balance Sheet Information and Fair Value - Marketable Securities (Detail) - USD ($) $ in Thousands	Feb. 29, 2016	Feb. 28, 2015
Schedule of Available-for-sale Securities [Line Items]
Marketable securities, Amortized Cost	$ 36,014	$ 40,767
Marketable securities, Gross Unrealized Gains	432	70
Marketable securities, Gross Unrealized Losses	(52)	(83)
Marketable securities, Fair Value	36,394	40,754
Asset-backed securities
Schedule of Available-for-sale Securities [Line Items]
Marketable securities, Amortized Cost	4,717	4,846
Marketable securities, Gross Unrealized Gains	9	3
Marketable securities, Gross Unrealized Losses	(3)	(4)
Marketable securities, Fair Value	4,723	4,845
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Marketable securities, Amortized Cost	19,135	21,241
Marketable securities, Gross Unrealized Gains	11	17
Marketable securities, Gross Unrealized Losses	(22)	(13)
Marketable securities, Fair Value	19,124	21,245
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Marketable securities, Amortized Cost	3,095	1,211
Marketable securities, Gross Unrealized Gains	380	37
Marketable securities, Gross Unrealized Losses	0	(32)
Marketable securities, Fair Value	3,475	1,216
Foreign government bonds
Schedule of Available-for-sale Securities [Line Items]
Marketable securities, Amortized Cost	205	201
Marketable securities, Fair Value	205	201
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Marketable securities, Amortized Cost	2,341	2,716
Marketable securities, Gross Unrealized Gains	0	4
Marketable securities, Gross Unrealized Losses	(13)	(10)
Marketable securities, Fair Value	2,328	2,710
U.S. government agency securities
Schedule of Available-for-sale Securities [Line Items]
Marketable securities, Amortized Cost	2,242	7,310
Marketable securities, Gross Unrealized Gains	6	8
Marketable securities, Gross Unrealized Losses	(14)	(24)
Marketable securities, Fair Value	2,234	7,294
U.S. government notes
Schedule of Available-for-sale Securities [Line Items]
Marketable securities, Amortized Cost	4,279	3,242
Marketable securities, Gross Unrealized Gains	26	1
Marketable securities, Fair Value	$ 4,305	$ 3,243

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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