Balance Sheet Information - Summary of Securities with Gross Unrealized Loss Positions and Fair Values (Detail) - USD ($) $ in Thousands	May 31, 2016	Feb. 29, 2016
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	$ 18,171	$ 16,509
Less Than 12 Months, Unrealized Losses	(52)	(43)
12 Months or Greater, Fair Value	483	1,007
12 Months or Greater, Unrealized Losses	(4)	(9)
Total, Fair Value	18,654	17,516
Total, Unrealized Losses	(56)	(52)
Asset-backed securities
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value		1,788
Less Than 12 Months, Unrealized Losses		(3)
12 Months or Greater, Fair Value		0
12 Months or Greater, Unrealized Losses		0
Total, Fair Value		1,788
Total, Unrealized Losses		(3)
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	10,924	12,088
Less Than 12 Months, Unrealized Losses	(20)	(22)
12 Months or Greater, Fair Value	0	0
12 Months or Greater, Unrealized Losses	0	0
Total, Fair Value	10,924	12,088
Total, Unrealized Losses	(20)	(22)
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	1,345	1,746
Less Than 12 Months, Unrealized Losses	(3)	(8)
12 Months or Greater, Fair Value	234	385
12 Months or Greater, Unrealized Losses	(2)	(5)
Total, Fair Value	1,579	2,131
Total, Unrealized Losses	(5)	(13)
U.S. government agency securities
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	5,332	887
Less Than 12 Months, Unrealized Losses	(27)	(10)
12 Months or Greater, Fair Value	249	622
12 Months or Greater, Unrealized Losses	(2)	(4)
Total, Fair Value	5,581	1,509
Total, Unrealized Losses	(29)	$ (14)
U.S. government notes
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	570
Less Than 12 Months, Unrealized Losses	(2)
12 Months or Greater, Fair Value	0
12 Months or Greater, Unrealized Losses	0
Total, Fair Value	570
Total, Unrealized Losses	$ (2)