Basic and Diluted Earnings Per Share (Details Textual) - USD ($) shares in Millions, $ in Millions |
3 Months Ended | 6 Months Ended | |||
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Nov. 30, 2015 |
Nov. 30, 2014 |
Nov. 30, 2015 |
Nov. 30, 2014 |
May. 31, 2014 |
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| Equity, Class of Treasury Stock [Line Items] | |||||
| Stock repurchased and retired during period, Shares | 0.0 | 0.4 | 1.3 | 1.3 | |
| Stock repurchased and retired during period, Value | $ 15.0 | $ 62.9 | $ 52.5 | ||
| Stock repurchase program, Authorized amount | $ 350.0 | ||||
| Common stock issued in connection with the exercise or vesting of stock-based awards | 0.4 | 0.7 | 1.1 | 1.4 | |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans. No definition available.
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- Definition Amount of stock repurchase plan authorized. No definition available.
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- Definition Number of shares that have been repurchased and retired during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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