Funds Held for Clients and Corporate Investments (Narrative) (Details) $ in Millions |
12 Months Ended | |
|---|---|---|
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May 31, 2016
USD ($)
security
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May 31, 2015
USD ($)
security
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| Schedule of Available-for-sale Securities [Line Items] | ||
| Net unrealized gain on available-for-sale securities | $ 47.6 | $ 13.6 |
| Number of available-for-sale securities in an unrealized loss position | security | 63 | 280 |
| Gross unrealized losses on available-for-sale securities | $ 0.7 | $ 7.5 |
| Variable Rate Demand Notes [Member] | Minimum [Member] | ||
| Schedule of Available-for-sale Securities [Line Items] | ||
| Available-for-sale securities contractual maturities | 20 years | |
| Variable Rate Demand Notes [Member] | Maximum [Member] | ||
| Schedule of Available-for-sale Securities [Line Items] | ||
| Available-for-sale securities contractual maturities | 30 years |
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- Definition Available-for-sale Securities, Debt Maturities, Term No definition available.
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- Definition Amount before tax of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. No definition available.
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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