Summary of Level 3 Activity (Detail) $ in Thousands	3 Months Ended
	Apr. 30, 2016 USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	$ 3,749
Payments	(1,475)
Adjustment	35
Interest accretion	32
Balance at ending of period	$ 2,341