Quarterly report [Sections 13 or 15(d)]

Service Revenue (Summary of Changes in Deferred Costs to Obtain and Fulfill Contracts) (Details)

v3.25.1
Service Revenue (Summary of Changes in Deferred Costs to Obtain and Fulfill Contracts) (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Feb. 28, 2025
Feb. 29, 2024
Feb. 28, 2025
Feb. 29, 2024
Capitalized Contract Cost [Line Items]        
Amortization     $ 176.6 $ 173.4
Costs To Fulfill Contracts [Member]        
Capitalized Contract Cost [Line Items]        
Balance, beginning of period $ 75.8 $ 75.8 76.6 75.3
Capitalization of costs 6.9 7.5 19.5 21.2
Amortization (6.7) (6.7) (20.1) (19.9)
Balance, end of period 76.0 76.6 76.0 76.6
Costs To Obtain Contracts [Member]        
Capitalized Contract Cost [Line Items]        
Balance, beginning of period 600.7 605.0 609.4 597.5
Capitalization of costs 59.0 53.7 154.2 163.1
Amortization (52.6) (51.6) (156.5) (153.5)
Balance, end of period $ 607.1 $ 607.1 $ 607.1 $ 607.1