Equity and Incentive Compensation Plans - Summary of Stock Option Activity (Rollforward) (Detail) (USD $)	12 Months Ended
	Jan. 31, 2015
Shares
Options outstanding at prior year-end	2,199,719
Granted	63,700	[1]
Exercise of options (in shares)	498,388
Forfeited and expired	67,808
Options outstanding at current year-end	1,697,223
Vested and exercisable at current year-end	1,474,576
Options expected to vest in the future as of current year-end	204,513
Weighted - Average Exercise Price
Options outstanding at prior year-end	$ 26.60
Granted, Weighted Average Exercise Price	$ 37.52	[1]
Exercises, Weighted Average Exercise Price	$ 29.00
Forfeitures and expirations, Weighted Average Exercise Price	$ 29.95
Options outstanding at current year-end	$ 26.17
Vested and exercisable at current year-end	$ 25.34
Options expected to vest in the future as of current year-end	$ 31.92

[1] Options granted during Fiscal 2014 vest annually over a three-year period and expire ten years after the grant date.