Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Fair Value of Financial Assets and Liabilities Measured on Recurring Basis (Detail)

v2.4.0.8
Fair Value Measurements - Fair Value of Financial Assets and Liabilities Measured on Recurring Basis (Detail) (USD $)
In Thousands, unless otherwise specified
Jul. 31, 2013
Jan. 31, 2013
Financial assets:    
Cash $ 109,721 $ 104,109
Money market accounts 3,684 2,612
Available for sale marketable securities:    
U.S. government agency issues - Current 5,022 6,104
Non-current marketable securities:    
U.S. government agency issues - Non current 7,126 7,169
Total 125,553 119,994
Other liabilities:    
Acquisition-related consideration 2,435 5,656
US Government Agency Issues Short Term [Member]
    
Available for sale marketable securities:    
U.S. government agency issues - Current 5,022 6,104
US Government Agency Issues Long Term [Member]
    
Non-current marketable securities:    
U.S. government agency issues - Non current 7,126 7,169
Fair Value, Inputs, Level 1 [Member]
    
Financial assets:    
Cash 109,721 104,109
Money market accounts 3,684 2,612
Non-current marketable securities:    
Total 125,553 119,994
Other liabilities:    
Acquisition-related consideration      
Fair Value, Inputs, Level 1 [Member] | US Government Agency Issues Short Term [Member]
    
Available for sale marketable securities:    
U.S. government agency issues - Current 5,022 6,104
Fair Value, Inputs, Level 1 [Member] | US Government Agency Issues Long Term [Member]
    
Non-current marketable securities:    
U.S. government agency issues - Non current 7,126 7,169
Fair Value, Inputs, Level 2 [Member]
    
Financial assets:    
Cash      
Money market accounts      
Non-current marketable securities:    
Total      
Other liabilities:    
Acquisition-related consideration      
Fair Value, Inputs, Level 2 [Member] | US Government Agency Issues Short Term [Member]
    
Available for sale marketable securities:    
U.S. government agency issues - Current      
Fair Value, Inputs, Level 2 [Member] | US Government Agency Issues Long Term [Member]
    
Non-current marketable securities:    
U.S. government agency issues - Non current      
Fair Value, Inputs, Level 3 [Member]
    
Financial assets:    
Cash      
Money market accounts      
Non-current marketable securities:    
Total      
Other liabilities:    
Acquisition-related consideration 2,435 5,656
Fair Value, Inputs, Level 3 [Member] | US Government Agency Issues Short Term [Member]
    
Available for sale marketable securities:    
U.S. government agency issues - Current      
Fair Value, Inputs, Level 3 [Member] | US Government Agency Issues Long Term [Member]
    
Non-current marketable securities:    
U.S. government agency issues - Non current