Quarterly report pursuant to Section 13 or 15(d)

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

v3.3.1.900
Fair Value Measurements - Fair Value of Financial Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($)
$ in Thousands
Oct. 31, 2015
Jan. 31, 2015
Available for sale marketable securities:    
Marketable securities, short-term $ 4,508 $ 7,516
Non-current marketable securities:    
Marketable securities, long-term 8,266 6,793
Total 15,903 15,884
Financial liabilities:    
Contingent consideration 1,979  
U.S. Treasury Notes and Bonds Conventional [Member]    
Available for sale marketable securities:    
Marketable securities, short-term 2,004 1,501
Non-current marketable securities:    
Marketable securities, long-term 6,765 4,286
U.S. Government Agency Issues Short Term [Member]    
Available for sale marketable securities:    
Marketable securities, short-term 2,504 6,015
U.S. Government Agency Issues Long Term [Member]    
Non-current marketable securities:    
Marketable securities, long-term 1,501 2,507
Money Market Accounts [Member]    
Financial assets:    
Cash and cash equivalents 3,129 1,575
Fair Value, Inputs, Level 1 [Member]    
Non-current marketable securities:    
Total 11,898 7,362
Fair Value, Inputs, Level 1 [Member] | U.S. Treasury Notes and Bonds Conventional [Member]    
Available for sale marketable securities:    
Marketable securities, short-term 2,004 1,501
Non-current marketable securities:    
Marketable securities, long-term 6,765 4,286
Fair Value, Inputs, Level 1 [Member] | Money Market Accounts [Member]    
Financial assets:    
Cash and cash equivalents 3,129 1,575
Fair Value, Inputs, Level 2 [Member]    
Non-current marketable securities:    
Total 4,005 8,522
Fair Value, Inputs, Level 2 [Member] | U.S. Government Agency Issues Short Term [Member]    
Available for sale marketable securities:    
Marketable securities, short-term 2,504 6,015
Fair Value, Inputs, Level 2 [Member] | U.S. Government Agency Issues Long Term [Member]    
Non-current marketable securities:    
Marketable securities, long-term 1,501 $ 2,507
Fair Value, Inputs, Level 3 [Member]    
Financial liabilities:    
Contingent consideration $ 1,979