Financial Liabilities Measured at Fair Value on a Recurring Basis (Detail) - USD ($) $ in Thousands	Apr. 30, 2016	Jan. 31, 2016
Fair Value, Liabilities Measured on Recurring and Nonrecurring Basis
Contingent consideration	$ 2,341	$ 3,749
Level 1 | Fair Value, Measurements, Recurring
Fair Value, Liabilities Measured on Recurring and Nonrecurring Basis
Contingent consideration	0	0
Level 2 | Fair Value, Measurements, Recurring
Fair Value, Liabilities Measured on Recurring and Nonrecurring Basis
Contingent consideration	0	0
Level 3 | Fair Value, Measurements, Recurring
Fair Value, Liabilities Measured on Recurring and Nonrecurring Basis
Contingent consideration	$ 2,341	$ 3,749