Derivative Instruments and Hedging Activities - Income Statement Impact (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Nov. 30, 2021	Nov. 30, 2020	Nov. 30, 2021	Nov. 30, 2020
Derivative [Line Items]
Derivative cash settlements interest expense	$ 0	$ 0	$ 0	$ 0
Derivative forward value gains (losses)			(72,562)	198,335
Derivative gains (losses)	46,086	81,287	(126,077)	141,563
Interest rate swaps
Derivative [Line Items]
Derivative cash settlements interest expense	(25,952)	(29,800)	(53,515)	(56,772)
Derivative forward value gains (losses)	72,038	111,087	(72,562)	198,335
Derivative gains (losses)	$ 46,086	$ 81,287	$ (126,077)	$ 141,563

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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