Income Taxes - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2013	Jul. 31, 2012
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ (120)	$ 115	$ (361)	$ 116
Effective income tax rate, continuing operations			18.00%
Effective income tax rate reconciliation, at federal statutory income tax rate			35.00%