STOCKHOLDERS' EQUITY - TREASURY STOCK (Details) - USD ($)
$ in Thousands
3 Months Ended
Apr. 30, 2016
Apr. 30, 2015
Jan. 31, 2016
Activity in Accumulated Other Comprehensive Loss      
Purchases of treasury stock (in shares) 500,000 0  
Purchases of treasury stock $ 17,162 $ 0  
Treasury stock, (in shares) 848,000   348,000
Treasury stock, cost $ 27,413   $ 10,251