Investment in Affiliates - Financial Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Oct. 31, 2013	Oct. 31, 2012	Oct. 31, 2013	Oct. 31, 2012
Income statement data:
Revenues	$ 42,270	$ 102,020	$ 176,217	$ 361,918
Gross profit	2,085	23,049	18,388	88,422
Operating (loss) income	(3,904)	13,879	(3,269)	54,116
Net (loss) income	$ (4,653)	$ 10,826	$ (7,825)	$ 41,640