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Retirement benefits - Weighted-Average Asset Allocation of Said Plan Assets for Pension Benefits (Detail) - Pension | Mar. 31, 2025
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Funds managed by trust |
Weighted-average asset allocation | 100.00%
Government Securities |
Funds managed by trust |
Weighted-average asset allocation | 89.30%
Debenture and bonds |
Funds managed by trust |
Weighted-average asset allocation | 10.70%
Other |
Funds managed by trust |
Weighted-average asset allocation | 0.00%

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- Definition 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 -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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