Pension Plan - Summary of Pension Expense Composed of Components Included in Cost of Goods Sold and Selling, General and Administrative Expenses (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	May 31, 2013	May 31, 2012
Components of net periodic benefit cost
Service cost	$ 315	$ 321
Interest cost	601	600
Expected return on plan assets	(872)	(802)
Amortization of:
Prior service cost	(36)	(36)
Unrecognized net loss	512	456
Net periodic benefit cost	$ 520	$ 539