Property, Plant And Equipment (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Property, Plant And Equipment [Abstract]
Capitalized interest included in property, plant and equipment	$ 6,197	$ 4,240	$ 4,469
Depreciation expense	220,580	218,649	223,453
Capital leases included in the property, plant and equipment, cost	7,803	8,113
Capital leases included in the property, plant and equipment, accumulated depreciation	$ 5,881	$ 5,420