Property, Plant and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Property, Plant and Equipment [Line Items]
Land	$ 11,804	$ 11,818
Land improvements	51,703	51,017
Buildings and improvements	249,801	238,031
Machinery and equipment	1,660,636	1,576,932
Office and other equipment	6,058	5,787
Construction in progress	98,258	60,932
Property, Plant and Equipment, Gross, Total	2,078,260	1,944,517
Less accumulated depreciation	(1,342,694)	(1,290,061)
Property, plant and equipment, net	$ 735,566	$ 654,456

The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.

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- Definition

Gross amount, as of the balance sheet date, of long-lived, depreciable assets that include building structures held for productive use including any addition, improvement, or renovation to the structure, such as interior masonry, interior flooring, electrical, and plumbing.

+ References

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- Definition

Gross amount, at the balance sheet date, of long-lived assets under construction that include construction costs to date on capital projects that have not been completed and assets being constructed that are not ready to be placed into service.

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- Definition

Carrying amount as of the balance sheet date of real estate held for productive use. This excludes land held for sale.

+ References

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- Definition

This element represents alterations to land which improves its potential for use. Generally consisting of items having limited lives, such as walkways, driveways, fences, and parking lots, such improvements are depreciated over the useful lives of the subject assets.

+ References

No definition available.

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- Definition

Gross amount, as of the balance sheet date, of long-lived, depreciable assets used in the production process to produce goods and services.

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- Definition

Gross amount, at the balance sheet date, of long-lived physical assets used in the normal conduct of business and not intended for resale. This can include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

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- Definition

Tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year; net of accumulated depreciation. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

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- Definition

This element represents capitalized assets classified as property, plant and equipment not otherwise defined in the taxonomy.

+ References

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