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Postretirement Benefits - Weighted-Average Assumptions used to Determine Benefit Obligations and Net Periodic Postretirement Cost (Detail) - Postretirement Benefits | 12 Months Ended
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May 31, 2025 | May 31, 2024 | May 31, 2023
Domestic |  |  |
Health Care Cost Trend Rates Assumptions [Line Items] |  |  |
Year-End Benefit Obligations, Discount rate | 5.17% | 5.50% |
Year-End Benefit Obligations, Current healthcare cost trend rate | 8.30% | 8.90% |
Year-End Benefit Obligations, Ultimate healthcare cost trend rate | 4.00% | 4.04% |
Year-End Benefit Obligation, Year ultimate healthcare cost trend rate will be realized | 2048 | 2049 |
Net Periodic Postretirement Cost, Discount rate | 5.50% | 5.20% | 4.36%
Net Periodic Postretirement Cost, Current healthcare cost trend rate | 8.90% | 6.00% | 6.23%
Net Periodic Postretirement Cost, Ultimate healthcare cost trend rate | 4.04% | 4.03% | 4.03%
Net Periodic Postretirement Cost, Year ultimate healthcare cost trend rate will be realized | 2049 | 2045 | 2045
Non-U.S. Plans |  |  |
Health Care Cost Trend Rates Assumptions [Line Items] |  |  |
Year-End Benefit Obligations, Discount rate | 4.88% | 5.03% |
Year-End Benefit Obligations, Current healthcare cost trend rate | 5.13% | 5.21% |
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 | 5.03% | 5.10% | 5.13%
Net Periodic Postretirement Cost, Current healthcare cost trend rate | 5.21% | 5.53% | 5.58%
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

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- Definition Defined Benefit Plan, Benefit Obligation, Current Health Care Cost Trend Rate + References No definition available. + Details
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- Definition Defined benefit plan year ultimate healthcare realized cost trend rate. + References No definition available. + Details
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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 1 -Subparagraph (k)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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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 Reference 1: 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 + Details
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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 1 -Subparagraph (l) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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