Short-Term Borrowings - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified			9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended
	Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2014 Revolving Credit Facility	Jan. 31, 2014 Revolving Credit Facility	Jan. 31, 2014 Maximum Revolving Credit Facility	Jan. 31, 2014 Maximum Revolving Credit Facility	Jan. 31, 2014 Minimum Revolving Credit Facility	Jan. 31, 2014 Minimum Revolving Credit Facility	Jan. 31, 2014 L I B O R Maximum Revolving Credit Facility	Jan. 31, 2014 L I B O R Minimum Revolving Credit Facility	Jan. 31, 2014 Base Rate Maximum Revolving Credit Facility	Jan. 31, 2014 Base Rate Minimum Revolving Credit Facility
Line of Credit Facility
Expiration date			May 24, 2017
Maximum borrowing capacity			$ 125,000	$ 125,000
Basis spread on variable rate									2.50%	2.00%	1.50%	1.00%
Amount outstanding	0	0
Unused capacity, commitment fee percentage					0.40%		0.30%
Adjusted quick ratio								1.00
Leverage ratio						2.00
Senior leverage ratio						0.90
Percentage of net current account receivable included in cash and account receivable ratio				42.00%
Cash and accounts receivable ratio								1.25
Maximum amount available for dividends and stock repurchase dollar limit				$ 50,000
Maximum amount available for dividend distribution and stock repurchase percent of cumulative net income				70.00%