Debt, Derivatives and Hedging Activities - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Feb. 28, 2023	Feb. 28, 2022	Feb. 28, 2023	Feb. 28, 2022	May 31, 2022
Debt Instrument [Line Items]
Debt, carrying value	$ 2,749,000,000		$ 2,749,000,000		$ 2,811,200,000
Debt, fair value	2,641,200,000		2,641,200,000		2,862,200,000
Repayments of commercial paper			62,200,000
Issuance of commercial paper			559,200,000
Amortization of interest rate lock agreements - decrease to other comprehensive income	1,500,000	$ 500,000	4,600,000	$ 1,400,000
Notional value	500,000,000		500,000,000		500,000,000
Commercial paper
Debt Instrument [Line Items]
Commercial paper	$ 199,000,000		$ 199,000,000		$ 261,200,000
Weighted average interest rate	4.79%		4.79%		1.20%
Debt term			90 days		90 days
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		500,000,000
Revolving credit facility amount outstanding	$ 0		$ 0		$ 0