Summary of Significant Accounting Policies - Product Warranty Roll-forward (Details) - USD ($) $ in Thousands	12 Months Ended
	Feb. 28, 2018	Feb. 28, 2017	Feb. 29, 2016
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance, beginning balance	$ 2,098	$ 2,915	$ 2,287
Warranty costs incurred	(2,225)	(1,947)	(2,570)
Additions charged to income	2,140	1,130	3,198
Balance, ending balance	$ 2,013	$ 2,098	$ 2,915