Investment Income, Net (Schedule of Investment Income, Net) (Details) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
May 31, 2017 |
Feb. 28, 2017 |
Nov. 30, 2016 |
Aug. 31, 2016 |
May 31, 2016 |
Feb. 29, 2016 |
Nov. 30, 2015 |
Aug. 31, 2015 |
May 31, 2017 |
May 31, 2016 |
May 31, 2015 |
|
| Investment Income, Net [Abstract] | |||||||||||
| Interest income on corporate funds | $ 9.9 | $ 8.4 | $ 7.8 | ||||||||
| Interest expense | (2.5) | (1.1) | (0.7) | ||||||||
| Net loss from equity-method investments | (2.2) | (2.8) | (0.7) | ||||||||
| Investment income, net | $ 1.6 | $ 1.2 | $ 0.9 | $ 1.5 | $ (0.2) | $ 1.7 | $ 1.6 | $ 1.4 | $ 5.2 | $ 4.5 | $ 6.4 |
| X | ||||||||||
- Definition This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of the cost of borrowed funds accounted for as interest expense. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The net amount of nonoperating interest income (expense). No definition available.
|
| X | ||||||||||
- Definition The aggregate amount of income from investments (for example, dividends) not considered a component of the entity's core operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|