Stock Based Compensation (Schedule Of Stock Options Activity) (Details)	3 Months Ended
	Apr. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Shares, Outstanding at January 31, 2013	502,225
Shares, Exercised	(169,246)
Shares, Canceled	(1,033)
Shares, Outstanding at April 30, 2013	331,946