Service Revenue (Summary of Changes in Deferred Costs to Obtain and Fulfill Contracts) (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Nov. 30, 2025 |
Nov. 30, 2024 |
Nov. 30, 2025 |
Nov. 30, 2024 |
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| Capitalized Contract Cost [Line Items] | ||||
| Amortization | $ 121.8 | $ 117.3 | ||
| Costs To Fulfill Contracts [Member] | ||||
| Capitalized Contract Cost [Line Items] | ||||
| Balance, beginning of period | $ 99.0 | $ 76.2 | 87.0 | 76.6 |
| Capitalization of costs | 20.0 | 6.3 | 39.6 | 12.6 |
| Amortization | (8.2) | (6.7) | (15.8) | (13.4) |
| Balance, end of period | 110.8 | 75.8 | 110.8 | 75.8 |
| Costs To Obtain Contracts [Member] | ||||
| Capitalized Contract Cost [Line Items] | ||||
| Balance, beginning of period | 605.1 | 602.9 | 609.0 | 609.4 |
| Capitalization of costs | 60.1 | 49.9 | 109.0 | 95.2 |
| Amortization | (53.2) | (52.1) | (106.0) | (103.9) |
| Balance, end of period | $ 612.0 | $ 600.7 | $ 612.0 | $ 600.7 |
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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