Pensions and Other Benefit Plans - Components of net periodic pension cost and net periodic postretirement benefit cost (Details) - Pension Plans |
12 Months Ended | ||
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Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2024 |
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| Defined Benefit Plan Disclosure [Line Items] | |||
| Discount rate | 4.79% | 4.75% | 4.82% |
| Expected long-term rate of return on plan assets | 5.06% | 5.05% | 5.27% |
| Rate of compensation increase on active plans | 2.96% | 3.00% | 3.00% |
| Interest crediting rates used in cash balance pension plans | 4.64% | 4.38% | 4.95% |
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Weighted-average interest crediting rate used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, cash balance and other defined benefit plans with promised interest crediting rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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