Postretirement Benefits - Weighted-Average Assumptions used to Determine Benefit Obligations and Net Periodic Postretirement Cost (Detail) - Postretirement Benefits	12 Months Ended
May 31, 2026	May 31, 2025	May 31, 2024
Domestic
Health Care Cost Trend Rates Assumptions [Line Items]
Year-End Benefit Obligations, Discount rate	5.18%	5.17%
Year-End Benefit Obligations, Current healthcare cost trend rate	7.60%	8.30%
Year-End Benefit Obligations, Ultimate healthcare cost trend rate	4.00%	4.00%
Year-End Benefit Obligation, Year ultimate healthcare cost trend rate will be realized	2048	2048
Net Periodic Postretirement Cost, Discount rate	5.17%	5.50%	5.20%
Net Periodic Postretirement Cost, Current healthcare cost trend rate	8.30%	8.90%	6.00%
Net Periodic Postretirement Cost, Ultimate healthcare cost trend rate	4.00%	4.04%	4.03%
Net Periodic Postretirement Cost, Year ultimate healthcare cost trend rate will be realized	2048	2049	2045
Non-U.S. Plans
Health Care Cost Trend Rates Assumptions [Line Items]
Year-End Benefit Obligations, Discount rate	4.98%	4.88%
Year-End Benefit Obligations, Current healthcare cost trend rate	5.07%	5.13%
Year-End Benefit Obligations, Ultimate healthcare cost trend rate	3.70%	3.70%
Year-End Benefit Obligation, Year ultimate healthcare cost trend rate will be realized	2040	2040
Net Periodic Postretirement Cost, Discount rate	4.88%	5.03%	5.10%
Net Periodic Postretirement Cost, Current healthcare cost trend rate	5.13%	5.21%	5.53%
Net Periodic Postretirement Cost, Ultimate healthcare cost trend rate	3.70%	3.70%	3.70%
Net Periodic Postretirement Cost, Year ultimate healthcare cost trend rate will be realized	2040	2040	2040

Defined Benefit Plan, Benefit Obligation, Current Health Care Cost Trend Rate

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- Definition

Defined Benefit Plan, Benefit Obligation, Ultimate Health Care Cost Trend Rate

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- Definition

Defined Benefit Plan, Ultimate Health Care Cost Trend Rate, Net Periodic Postretirement Benefit Cost

+ References

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- Definition

Defined benefit plan year ultimate healthcare realized cost trend rate.

+ References

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- Definition

Health Care Cost Trend Rate used to Determine Net Period Benefit Cost

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Health Care Cost Trend Rates Assumptions [Line Items]

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (j)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

+ References

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- Definition

Year ultimate health care cost trend rate is expected to be reached, in YYYY format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (k)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (l)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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