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Employee Benefit Plans - Weighted Average Actuarial Assumptions Used to Develop Projected Benefit Obligation (Detail) - Other Postretirement Benefit Plans [Member] | Mar. 31, 2016 | Mar. 31, 2015
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Defined Benefit Plan Disclosure [Line Items] |  |
Discount rate | 3.16% | 3.11%
Medical care cost trend rate | 8.00% | 8.00%

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- Definition Expected rate used to calculate the benefit obligation medical care cost trend rate. + References No definition available. + Details
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- Definition The interest rate used to adjust for the time value of money for the plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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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. + References No definition available. + Details
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- Details
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