XML 97 R79.htm IDEA: XBRL DOCUMENT v3.7.0.1
Stock And Stock-Based Incentive Plans (Assumptions Used To Estimate Option Values) (Details)
12 Months Ended
Feb. 28, 2017
Feb. 29, 2016
Feb. 28, 2015
Share-based Compensation [Abstract]      
Dividend yield 0.00% 0.00% 0.00%
Expected volatility factor, Minimum 29.30% 25.80% 25.20%
Expected volatility factor, Maximum 34.80% 31.80% 32.70%
Weighted average expected volatility 30.70% 30.60% 31.80%
Risk-free interest rate, Minimum 0.12% 0.00% 0.01%
Risk-free interest rate, Maximum 2.40% 2.10% 2.70%
Expected term (in years) 4 years 7 months 4 years 8 months 4 years 8 months