Discontinued Operations (Detail) - Consolidated Condensed Statements of Operations that were reclassified as discontinued operations (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Oct. 31, 2012	Oct. 31, 2011	Oct. 31, 2012	Oct. 31, 2011
Net sales and revenue	$ 434	$ 921	$ 1,549	$ 3,411
Cost of sales	52	194	361	741
Income before income taxes	179	298	601	1,401
Provision for income taxes	(72)	(112)	(240)	(545)
Income from discontinued operations, net of tax	107	186	361	856
Gain on disposal	50	429	133	695
Provision for income taxes	(20)	(162)	(53)	(270)
Gain on disposal of discontinued operations, net of tax	$ 30	$ 267	$ 80	$ 425