Stock-Based Compensation Plans (Details 2) - Employee Stock Option [Member] - USD ($) $ in Millions |
12 Months Ended | ||
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May. 31, 2015 |
May. 31, 2014 |
May. 31, 2013 |
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| Stock options, other information | |||
| Total intrinsic value of stock options exercised | $ 17.6 | $ 18.9 | $ 7.8 |
| Total grant-date fair value of stock options vested | $ 3.6 | $ 3.0 | $ 3.0 |
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- Definition Schedule of share based payment award stock options other information. No definition available.
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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