Provision for Income Taxes (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Apr. 30, 2014	Apr. 30, 2013
Disclosure Provision For Income Taxes Abstract
Income tax expense (benefit)	$ (174)	$ 568
Effective tax rate	5.40%	381.00%
Period specific tax items	10
Effective income tax rate forecast	11.00%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	35.00%
Unrecognized Tax Benefits	$ 21,047