Accumulated Other Comprehensive Income (Changes in Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
May 31, 2017 |
May 31, 2016 |
May 31, 2015 |
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| Accumulated Other Comprehensive Income [Abstract] | |||
| Beginning balance | $ 29.2 | $ 7.5 | $ 21.5 |
| Unrealized holding (losses)/gains | (14.7) | 34.2 | (21.5) |
| Income tax benefit/(expense) related to unrealized holding (losses)/gains | 5.6 | (12.4) | 7.7 |
| Reclassification adjustment for the net gain on sale of available-for-sale securities realized in net income | (0.1) | (0.1) | (0.3) |
| Income tax expense on reclassification adjustment for the net gain on sale of available-for-sale securities | 0.1 | ||
| Total other comprehensive (loss)/income, net of tax | (9.2) | 21.7 | (14.0) |
| Ending balance | 20.0 | 29.2 | 7.5 |
| Total tax (benefit)/expense included in other comprehensive (loss)/income | $ (5.6) | $ 12.4 | $ (7.8) |
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- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after tax of other comprehensive income (loss) attributable to parent entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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