Property, Plant and Equipment (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment
Gross property, plant and equipment	$ 3,248,103	$ 3,288,630
Less: Accumulated depreciation	(2,008,435)	(2,022,405)
Property, plant and equipment, net	1,239,668	1,266,225
Land
Property, Plant and Equipment
Gross property, plant and equipment	25,645	26,336
Land improvements
Property, Plant and Equipment
Gross property, plant and equipment	14,279	14,199
Buildings and improvements
Property, Plant and Equipment
Gross property, plant and equipment	195,349	190,078
Machinery and equipment
Property, Plant and Equipment
Gross property, plant and equipment	2,905,105	2,950,384
Uncompleted construction
Property, Plant and Equipment
Gross property, plant and equipment	$ 107,725	$ 107,633

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.

+ References+ Details

Gross amount of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References+ Details

- Definition

Amount, net of accumulated depreciation, depletion and amortization, of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References+ Details