Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2011
Schedule Of Income Taxes [Line Items]
Undistributed foreign earnings	$ 474,000,000	$ 403,000,000
Expected increase in U.S. Federal income taxes upon distributed of earnings	87,000,000	71,000,000
State tax loss carryforwards	7,000,000
Foreign tax loss carryforwards	107,000,000
Unrecognized tax benefits that would impact effective tax rate	17,564,000	12,998,000	11,605,000
Recognized expense associated with interest and penalties	650,000	3,924,000	1,184,000
Accrued interest and penalties within accounts payable and accrued liabilities	7,878,000	7,228,000
Unrecognized tax benefits, decreases resulting from current period tax positions	$ 20,000,000