Employee Benefit Plans - Weighted Average Actuarial Assumptions Used to Develop Projected Benefit Obligation (Detail) - Other Postretirement Benefit Plans [Member] |
12 Months Ended | |
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Mar. 31, 2017 |
Mar. 31, 2016 |
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| Defined Benefit Plan Disclosure [Line Items] | ||
| Discount rate | 3.23% | 3.16% |
| Medical care cost trend rate | 8.00% | 8.00% |
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- Definition The interest rate used to adjust for the time value of money for the plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. No definition available.
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- Definition The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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