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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, 2014 | Mar. 31, 2013
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Other Postretirement Benefit Plans [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Discount rate | 3.59% | 3.26%
Medical care cost trend rate | 8.00% | 8.00%

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- Definition Defined benefit plan assumptions used calculating 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=28361610&loc=d3e1928-114920 + Details
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- Details
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