Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Aug. 31, 2016	Aug. 31, 2015	Aug. 31, 2016	Aug. 31, 2015
Numerator:
Net income for basic and diluted earnings per common share	$ 10,023	$ 17,243	$ 31,086	$ 37,167
Denominator:
Denominator for basic earnings per common share-weighted average shares (shares)	25,987	25,782	25,950	25,769
Effect of dilutive securities:
Employee and Director stock awards (shares)	132	140	131	123
Denominator for diluted earnings per common share (shares)	26,119	25,922	26,081	25,892
Earnings per share basic and diluted:
Basic earnings per Common share (usd per share)	$ 0.39	$ 0.67	$ 1.20	$ 1.44
Diluted earnings per common share (usd per share)	$ 0.38	$ 0.67	$ 1.19	$ 1.44