Goodwill and Intangible Assets - Schedule of Intangible Assets Subject to Amortization (Detail) - USD ($) $ in Thousands	Aug. 31, 2017	Feb. 28, 2017
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 74,140	$ 73,560
Accumulated Amortization	(45,643)	(41,609)
Net Carrying Value	28,497	31,951
Acquired developed technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	50,296	50,013
Accumulated Amortization	(32,626)	(30,105)
Net Carrying Value	17,670	19,908
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	20,033	19,736
Accumulated Amortization	(10,594)	(9,348)
Net Carrying Value	9,439	10,388
Patents
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,999	2,999
Accumulated Amortization	(1,991)	(1,781)
Net Carrying Value	1,008	1,218
Trade name
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	812	812
Accumulated Amortization	(432)	(375)
Net Carrying Value	$ 380	$ 437