NET INCOME PER SHARE FROM CONTINUING OPERATIONS (Detail) - Schedule of Earnings Per Share, Basic and Diluted (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2011
Basic net income per share from continuing operations attributable to REX common shareholders (in Dollars)		$ 26,629	$ 18,614
Basic net income per share from continuing operations attributable to REX common shareholders	8,272	9,117	9,651
Basic net income per share from continuing operations attributable to REX common shareholders (in Dollars per share)	$ (0.35)	$ 2.92	$ 1.93
Effect of stock options		70	174
Diluted net income per share from continuing operations attributable to REX common shareholders (in Dollars)		$ 26,629	$ 18,614
Diluted net income per share from continuing operations attributable to REX common shareholders	8,272	9,187	9,825
Diluted net income per share from continuing operations attributable to REX common shareholders (in Dollars per share)	$ (0.35)	$ 2.90	$ 1.89