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Summary of Significant Accounting Policies - Estimated Useful Lives of Various Classes of Assets (Detail) | 12 Months Ended
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Mar. 31, 2015
Buildings |
Property, Plant and Equipment [Line Items] |
Estimated useful lives | 20 years
Machinery and Equipment |
Property, Plant and Equipment [Line Items] |
Estimated useful lives | 10 years
Yard improvements | Minimum |
Property, Plant and Equipment [Line Items] |
Estimated useful lives | 5 years
Yard improvements | Maximum |
Property, Plant and Equipment [Line Items] |
Estimated useful lives | 10 years
Loaders and other rolling stock | Minimum |
Property, Plant and Equipment [Line Items] |
Estimated useful lives | 5 years
Loaders and other rolling stock | Maximum |
Property, Plant and Equipment [Line Items] |
Estimated useful lives | 10 years

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- Details
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- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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- Details
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- Details
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- Details
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