Share-Based Compensation Plans (Details 2) - Stock Options $ / shares in Units, $ in Millions	9 Months Ended
	Oct. 31, 2015 USD ($) $ / shares shares
Shares
Outstanding at the beginning of the period (in shares) | shares	660,283
Granted (in shares) | shares	41,951
Exercised (in shares) | shares	(19,617)
Outstanding at the end of the period (in shares) | shares	682,617
Exercisable at the end of the period (in shares) | shares	301,070
Weighted-Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)	$ 38.28
Granted (in dollars per share)	57.91
Exercised (in dollars per share)	33.02
Outstanding at the end of the period (in dollars per share)	39.64
Exercisable at the end of the period (in dollars per share)	31.83
Additional disclosures
Weighted-average grant date fair value of stock options granted (in dollars per share)	$ 18.63
Assumptions used to value stock options
Risk-free interest rate (as a percent)	1.51%
Expected lives	5 years
Dividend yield (as a percent)	1.38%
Expected volatility (as a percent)	39.74%
Unrecognized compensation cost
Unrecognized compensation cost related to non-vested stock options | $	$ 3.9
Compensation recognition period	1 year 6 months