STOCK-BASED COMPENSATION STOCK-BASED COMPENSATION - STOCK-BASED COMPENSATION - BY LINE ITEM (Details) - USD ($)
$ in Thousands
3 Months Ended
Apr. 30, 2016
Apr. 30, 2015
Stock-Based Compensation Plans    
Stock-based compensation expense $ 15,340 $ 14,850
Cost of revenue - product    
Stock-Based Compensation Plans    
Stock-based compensation expense 113 135
Cost of revenue - service and support    
Stock-Based Compensation Plans    
Stock-based compensation expense 1,391 461
Research and development, net    
Stock-Based Compensation Plans    
Stock-based compensation expense 1,462 1,263
Selling, general and administrative    
Stock-Based Compensation Plans    
Stock-based compensation expense $ 12,374 $ 12,991