CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Parenthetical) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 9 Months Ended
Oct. 31, 2012
Oct. 31, 2011
Oct. 31, 2012
Oct. 31, 2011
stock-based compensation expense     $ 11,223 $ 2,267
Cost of revenues
       
stock-based compensation expense 322 37 697 83
Research and development
       
stock-based compensation expense 1,560 229 3,722 531
Sales and marketing
       
stock-based compensation expense 2,093 405 4,456 829
General and administrative
       
stock-based compensation expense $ 710 $ 370 $ 2,348 $ 824