Stock-Based Compensation Plans (Tables)
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12 Months Ended |
May 31, 2016 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
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| Weighted-Average Assumptions |
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Year ended May 31,
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2014
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2016
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2015
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2014
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Performance stock options
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Stock options
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Risk-free interest rate
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1.5
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%
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1.9
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%
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2.1
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%
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2.0
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%
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Dividend yield
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3.9
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%
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3.6
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%
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3.7
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%
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4.1
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%
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Volatility factor
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0.20
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0.18
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0.21
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0.22
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Expected option life in years
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4.5
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6.1
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6.0
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6.4
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Weighted-average grant-date
fair value of stock options granted (per share)
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$
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3.85
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$
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5.25
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$
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5.68
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$
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4.90
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| Stock Option Activity |
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Weighted-
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Weighted-
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average
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Shares
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average
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remaining
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Aggregate
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subject
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exercise price
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contractual
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intrinsic
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In millions, except per share amounts
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to options
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per share
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term (years)
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value(1)
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Outstanding as of May 31, 2015
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4.7
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$
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35.21
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Granted
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0.8
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$
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47.42
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Exercised
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(0.9)
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$
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34.77
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Forfeited
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(0.1)
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$
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38.46
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Expired
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—
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$
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35.89
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Outstanding as of May 31, 2016
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4.5
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$
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37.42
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6.3
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$
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75.9
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Exercisable as of May 31, 2016
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2.6
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$
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33.84
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4.9
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$
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53.1
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(1)
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Market price of the underlying stock as of May 31, 2016 less the exercise price.
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| Other Information Pertaining to Stock Option Grants |
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Year ended May 31,
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In millions, except per share amounts
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2016
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2015
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2014
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Total intrinsic value of stock options exercised
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$
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14.5
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$
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17.6
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$
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18.9
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Total grant-date fair value of stock options vested
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$
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4.0
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$
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3.6
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$
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3.0
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| RSU Activity |
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Weighted-
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Weighted-
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average
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average
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remaining
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grant-date
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vesting
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Aggregate
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fair value
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period
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intrinsic
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In millions, except per share amounts
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RSUs
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per share
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(years)
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value(1)
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Nonvested as of May 31, 2015
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1.8
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$
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33.57
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Granted
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0.7
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$
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42.60
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Vested
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(0.5)
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$
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31.34
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Forfeited
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(0.2)
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$
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35.97
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Nonvested as of May 31, 2016
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1.8
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$
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37.58
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3.0
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$
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96.5
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(1)
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Intrinsic value for RSUs is the market price of the underlying stock as of May 31, 2016.
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| Other Information Pertaining to RSUs |
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Year ended May 31,
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In millions, except per share amounts
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2016
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2015
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2014
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Weighted-average grant-date fair value of RSUs granted
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$
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42.60
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$
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36.64
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$
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36.37
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Total intrinsic value of RSUs vested
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$
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25.9
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$
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21.7
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$
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18.3
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Total grant-date fair value of RSUs vested
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$
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17.3
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$
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14.8
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$
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12.1
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| Restricted Stock Activity |
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Weighted-
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average
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grant-date
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Restricted
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fair value
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In millions, except per share amounts
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shares
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per share
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Nonvested as of May 31, 2015
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0.2
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$
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38.99
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Granted
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—
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$
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47.46
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Vested
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(0.1)
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$
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37.70
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Forfeited
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—
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$
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40.54
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Nonvested as of May 31, 2016
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0.1
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$
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43.99
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| Other Information Pertaining to Restricted Stock |
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Year ended May 31,
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In millions, except per share amounts
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2016
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2015
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2014
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Weighted-average grant-date fair value of restricted stock granted
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$
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47.46
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$
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41.70
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$
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38.53
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Total grant-date fair value of restricted stock vested
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$
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3.0
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$
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3.5
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$
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3.3
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| Performance Share Activity |
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Weighted-
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average
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grant-date
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Performance
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fair value
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In millions, except per share amounts
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shares
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per share
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Nonvested as of May 31, 2015
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0.6
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$
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34.24
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Granted (1)
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0.1
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$
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42.48
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Vested
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(0.2)
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$
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29.10
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Forfeited
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—
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$
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37.09
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Nonvested as of May 31, 2016
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0.5
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$
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38.89
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(1)
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Performance shares granted assuming achievement of performance goals at target. Actual amount of shares to be earned may differ from this amount.
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| Performance Awards [Member] |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
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| Stock Option Activity |
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Weighted-
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Weighted-
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average
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Shares
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average
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remaining
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Aggregate
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|
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subject
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exercise price
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contractual
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intrinsic
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In millions, except per share amounts
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to options
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per share
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term (years)
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value(1)
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Outstanding as of May 31, 2015
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2.7
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$
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31.31
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Granted
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—
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$
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—
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Exercised
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(0.1)
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$
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31.11
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Forfeited
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(0.1)
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$
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29.85
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Expired
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—
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$
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—
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Outstanding as of May 31, 2016
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2.5
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$
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31.36
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5.4
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$
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57.9
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Exercisable as of May 31, 2016
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0.4
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$
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31.22
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5.2
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$
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9.6
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(1)
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Market price of the underlying stock as of May 31, 2016 less the exercise price.
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