Derivative Instruments and Hedging Activities - Schedule of derivative notional amount and weighted-average rates (Details) - USD ($) $ in Thousands	May 31, 2023	May 31, 2022
Interest rate swaps
Derivative [Line Items]
Notional Amount	$ 7,816,114	$ 8,061,631
Pay-fixed swaps and Receive-fixed swaps, Subtotal
Derivative [Line Items]
Notional Amount	$ 7,620,269	$ 7,937,631
Weighted- Average Rate Paid	3.49%	2.33%
Weighted- Average Rate Received	4.75%	1.64%
Pay-fixed swaps
Derivative [Line Items]
Notional Amount	$ 5,920,269	$ 5,957,631
Weighted- Average Rate Paid	2.75%	2.60%
Weighted- Average Rate Received	5.26%	1.24%
Receive-fixed swaps
Derivative [Line Items]
Notional Amount	$ 1,700,000	$ 1,980,000
Weighted- Average Rate Paid	6.05%	1.53%
Weighted- Average Rate Received	2.97%	2.86%
Forward pay-fixed swaps
Derivative [Line Items]
Notional Amount	$ 195,845	$ 124,000