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Comprehensive Income (Details) (USD $)
In Millions, unless otherwise specified |
3 Months Ended | 6 Months Ended | |||
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Nov. 30, 2011
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Nov. 30, 2010
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Nov. 30, 2011
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Nov. 30, 2010
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May 31, 2011
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| Comprehensive Income [Abstract] | |||||
| Net income | $ 140.4 | $ 133.9 | $ 289.3 | $ 265.8 | |
| Other comprehensive loss: | |||||
| Unrealized losses on available-for-sale securities, net of tax | (10.1) | (14.9) | (3.4) | (3.1) | |
| Reclassification adjustment for the net gain on sale of available-for-sale securities realized in net income, net of tax | (0.1) | (0.2) | (0.2) | (0.2) | |
| Total other comprehensive loss | (10.2) | (15.1) | (3.6) | (3.3) | |
| Total comprehensive income | 130.2 | 118.8 | 285.7 | 262.5 | |
| Comprehensive Income (Textuals) [Abstract] | |||||
| Accumulated other comprehensive income | 33.9 | 33.9 | 37.5 | ||
| Accumulated other comprehensive income, tax amount | $ 19.7 | $ 19.7 | $ 21.7 | ||
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- Definition
Accumulated other comprehensive income, tax amount. No definition available.
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- Details
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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
The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
This element represents Other Comprehensive Income or Loss, Net of Tax, for the period attributable to the parent entity. Includes deferred gains or losses on qualifying hedges, unrealized holding gains or losses on available-for-sale securities, minimum pension liability, and cumulative translation adjustment. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
Reclassification adjustment for unrealized gains or losses realized upon the sale of securities, after tax. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Appreciation or loss in value (before reclassification adjustment) of the total of unsold securities during the period being reported on, net of tax. Reclassification adjustments include: (1) the unrealized holding gain (loss), net of tax, at the date of the transfer for a debt security from the held-to-maturity category transferred into the available-for-sale category. Also includes the unrealized gain (loss) at the date of transfer for a debt security from the available-for-sale category transferred into the held-to-maturity category; (2) the unrealized gains (losses) realized upon the sale of securities, after tax; and (3) the unrealized gains (losses) realized upon the write-down of securities, after tax. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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