Annual report pursuant to Section 13 and 15(d)

Stock-Based Employee Compensation (Details 3)

v3.7.0.1
Stock-Based Employee Compensation (Details 3) - Long Term Stock Incentive Plan [Member] - Stock options [Member] - $ / shares
12 Months Ended
Feb. 28, 2017
Feb. 29, 2016
Feb. 28, 2015
Weighted average assumptions to estimate fair value of equity instruments using Black-Scholes option-pricing model      
Grant-date fair value $ 40.09 $ 31.14 $ 27.77
Expected life 5 years 11 months 5 years 11 months 5 years 11 months
Expected volatility 27.10% 28.50% 32.40%
Risk-free interest rate 1.60% 1.60% 2.10%
Expected dividend yield 1.00% 1.10% 0.00%