Quarterly report pursuant to Section 13 or 15(d)

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

v3.21.2
Service Revenue (Summary of Changes in Deferred Costs to Obtain and Fulfill Contracts) (Details) - USD ($)
$ in Millions
 3 Months Ended
Aug. 31, 2021
Aug. 31, 2020
Capitalized Contract Cost [Line Items]    
Amortization $ 49.1 $ 47.3
Costs To Fulfill Contracts [Member]    
Capitalized Contract Cost [Line Items]    
Balance, beginning of period 69.3 67.3
Capitalization of costs 7.1 6.1
Amortization (6.2) (5.9)
Balance, end of period 70.2 67.5
Costs To Obtain Contracts [Member]    
Capitalized Contract Cost [Line Items]    
Balance, beginning of period 488.2 473.6
Capitalization of costs 46.6 37.2
Amortization (42.9) (41.4)
Balance, end of period $ 491.9 $ 469.4