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Summary of Significant Accounting Policies (Details)	12 Months Ended
	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

X

- Details

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X

- 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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