Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Aug. 31, 2017	Aug. 31, 2016	Aug. 31, 2017	Aug. 31, 2016	Feb. 28, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Other intangible assets not subject to amortization	$ 0.2		$ 0.2		$ 0.2
Amortization expense	1.8	$ 1.8	3.5	$ 3.7
Amortization expense for the remainder of fiscal year 2018	3.4		3.4
Amortization expense for fiscal year 2019	6.0		6.0
Amortization expense for fiscal year 2020	5.8		5.8
Amortization expense for fiscal year 2021	5.3		5.3
Amortization expense for fiscal year 2022	4.9		4.9
Amortization expense thereafter	$ 3.1		$ 3.1