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Summary of Significant Accounting Policies - Estimated Useful Lives of Assets (Detail)	12 Months Ended
	Dec. 31, 2015
Minimum [Member] | Buildings and Improvements [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	10 years
Minimum [Member] | Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	5 years
Minimum [Member] | Rolling Stock [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	5 years
Minimum [Member] | Containers [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	5 years
Minimum [Member] | Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	3 years
Maximum [Member] | Buildings and Improvements [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	30 years
Maximum [Member] | Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	10 years
Maximum [Member] | Rolling Stock [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	10 years
Maximum [Member] | Containers [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	12 years
Maximum [Member] | Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, estimated useful life	8 years

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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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- 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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