Fair Value Measurements - Assets Measured at Fair Value as of Measurement Date (Detail) (Fair Value, Measurements, Recurring [Member], Deferred Compensation Plan Assets [Member], USD $) In Thousands, unless otherwise specified	Feb. 28, 2013	Feb. 29, 2012
Assets measured on a recurring and non-recurring basis:
Assets measured on a recurring basis	$ 10,636	$ 9,198
Quoted prices in active markets for identical assets (Level 1) [Member]
Assets measured on a recurring and non-recurring basis:
Assets measured on a recurring basis	9,175	7,756
Level 2 [Member]
Assets measured on a recurring and non-recurring basis:
Assets measured on a recurring basis	1,461	1,442
Level 3 [Member]
Assets measured on a recurring and non-recurring basis:
Assets measured on a recurring basis