Service Revenue (Summary of Changes in Deferred Costs to Obtain and Fulfill Contracts) (Details) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Aug. 31, 2020 |
Aug. 31, 2019 |
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| Capitalized Contract Cost [Line Items] | ||
| Amortization | $ 47.3 | $ 46.0 |
| Costs To Obtain A Contract [Member] | ||
| Capitalized Contract Cost [Line Items] | ||
| Beginning balance | 473.6 | 464.3 |
| Capitalization of costs | 37.2 | 35.9 |
| Amortization | (41.4) | (40.2) |
| Ending balance | 469.4 | 460.0 |
| Costs To Fulfill A Contract [Member] | ||
| Capitalized Contract Cost [Line Items] | ||
| Beginning balance | 67.3 | 66.1 |
| Capitalization of costs | 6.1 | 6.0 |
| Amortization | (5.9) | (5.8) |
| Ending balance | $ 67.5 | $ 66.3 |
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- Definition Capitalized Contract Cost No definition available.
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- Definition Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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- Definition Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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