Employee Benefit Plans - Asset Allocations in the Pension Plan (Details)	May 31, 2022	May 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Target Asset Allocation	100.00%
Actual Asset Allocation	100.00%	100.00%
Large cap equity
Defined Benefit Plan Disclosure [Line Items]
Target Asset Allocation	26.00%
Actual Asset Allocation	29.10%	29.80%
Small cap equity
Defined Benefit Plan Disclosure [Line Items]
Target Asset Allocation	5.00%
Actual Asset Allocation	6.20%	6.00%
International equity
Defined Benefit Plan Disclosure [Line Items]
Target Asset Allocation	8.00%
Actual Asset Allocation	8.20%	8.30%
Fixed income
Defined Benefit Plan Disclosure [Line Items]
Target Asset Allocation	45.00%
Actual Asset Allocation	43.20%	44.10%
Absolute return strategy funds
Defined Benefit Plan Disclosure [Line Items]
Target Asset Allocation	16.00%
Actual Asset Allocation	12.70%	11.30%
Cash
Defined Benefit Plan Disclosure [Line Items]
Target Asset Allocation	0.00%
Actual Asset Allocation	0.60%	0.50%

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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