Quarterly report pursuant to Section 13 or 15(d)

Share-Based Compensation Plans (Details 2)

v3.3.1.900
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