Debt, Derivatives and Hedging Activities - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Nov. 30, 2025	Nov. 30, 2024	Nov. 30, 2025	Nov. 30, 2024	May 31, 2025
Debt Instrument [Line Items]
Long-term debt, carrying amount	$ 2,436,600,000		$ 2,436,600,000		$ 2,436,600,000
Debt, fair value	2,445,400,000		2,445,400,000		2,404,700,000
Notional value	500,000,000		500,000,000		500,000,000
Accumulated Other Comprehensive Income
Debt Instrument [Line Items]
Amortization of interest rate lock agreements - decrease to other comprehensive income	1,500,000	$ 1,500,000	3,000,000.0	$ 3,000,000.0
Commercial paper
Debt Instrument [Line Items]
Debt due within one year	550,750,000	$ 181,000,000	$ 550,750,000	$ 181,000,000	0
Interest rate			4.09%
Debt due within one year					0
Revolving credit facility
Debt Instrument [Line Items]
Revolving credit facility, maximum borrowing capacity with accordion feature	2,000,000,000		$ 2,000,000,000
Debt amendment, increase limit (up to)	500,000,000.0		500,000,000.0
Revolving credit facility amount outstanding	$ 0		$ 0		$ 0