Stock-Based Benefit Plans (Details 2) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended			12 Months Ended
	Jan. 31, 2012	Jan. 31, 2011	Jan. 31, 2012 Performance Based Restricted Stock Units [Member]	Oct. 31, 2012 Performance Based Restricted Stock Units [Member]
Performance-Based Restricted Stock Units
Issuance of restricted stock and stock units, shares				350,000
Closing price of the Company's common stock on date of issuance				$ 20.50
Estimated aggregate fair value of performance-based RSUs issued (in thousands)				$ 7,185
RSU expense recognized	5,626	5,373	936
Unamortized value of performance-based RSUs at January 31, 2012			$ 6,249