Funds Held for Clients and Corporate Investments (Narrative) (Details) $ in Millions |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
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Feb. 28, 2019
USD ($)
security
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Feb. 28, 2018
USD ($)
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Feb. 28, 2019
USD ($)
security
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Feb. 28, 2018
USD ($)
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May 31, 2018
USD ($)
security
|
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| Schedule of Available-for-sale Securities [Line Items] | |||||
| Net unrealized losses on available-for-sale securities | $ 9.8 | $ 9.8 | $ 38.3 | ||
| Number of available-for-sale securities in an unrealized loss position | security | 667 | 667 | 970 | ||
| Gross unrealized losses on available-for-sale securities | $ 17.8 | $ 17.8 | $ 40.7 | ||
| Realized gains (losses) on available-for-sale securities | $ 0.4 | $ (0.2) | $ 0.5 | $ (0.6) | |
| 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 The net unrealize loss in the difference between the fair value and the carrying value of available for sale securities that are recognized in AOCI. 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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities. No definition available.
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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://fasb.org/us-gaap/role/ref/legacyRef
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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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