Derivative Instruments and Hedging Activities - Income Statement Impact (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Feb. 28, 2022	Feb. 28, 2021	Feb. 28, 2022	Feb. 28, 2021
Derivative [Line Items]
Derivative cash settlements interest expense	$ 0	$ 0	$ 0	$ 0
Derivative forward value gains			122,930	558,266
Derivative gains	169,280	330,196	43,203	471,759
Interest rate swaps
Derivative [Line Items]
Derivative cash settlements interest expense	(26,212)	(29,735)	(79,727)	(86,507)
Derivative forward value gains	195,492	359,931	122,930	558,266
Derivative gains	$ 169,280	$ 330,196	$ 43,203	$ 471,759

Interest Expense on Derivatives

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

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