Property, Plant and Equipment (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Property, plant and equipment
Land	$ 2,010	$ 1,432
Building improvements	564,465	520,137
Machinery and equipment	314,031	246,584
Capitalized leases for machinery, equipment and buildings	40,621	76,244
Property, plant and equipment, gross	921,127	844,397
Accumulated depreciation and amortization	(292,685)	(235,528)
Property Plant and Equipment Net before Construction in Progress	628,442	608,869
Construction in Progress	62,777	78,807
Property, plant and equipment, net	$ 691,219	$ 687,676