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Summary of Significant Accounting Policies (Details) | 12 Months Ended
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Dec. 31, 2012
Maximum [Member] | Land improvements [Member] |
Estimated useful lives by major classes of property and equipment |
Estimated useful lives of property and equipment | 30 years
Maximum [Member] | Buildings [Member] |
Estimated useful lives by major classes of property and equipment |
Estimated useful lives of property and equipment | 40 years
Maximum [Member] | Machinery and equipment [Member] |
Estimated useful lives by major classes of property and equipment |
Estimated useful lives of property and equipment | 30 years
Minimum [Member] | Land improvements [Member] |
Estimated useful lives by major classes of property and equipment |
Estimated useful lives of property and equipment | 15 years
Minimum [Member] | Buildings [Member] |
Estimated useful lives by major classes of property and equipment |
Estimated useful lives of property and equipment | 20 years
Minimum [Member] | Machinery and equipment [Member] |
Estimated useful lives by major classes of property and equipment |
Estimated useful lives of property and equipment | 3 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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