Property and Equipment, Net (Schedule of Property and Equipment, Net) (Details) - USD ($) $ in Thousands	Mar. 31, 2015	Dec. 31, 2014
Property and Equipment [Line Items]
Property and equipment	$ 1,099,300	$ 1,088,700
Less accumulated depreciation and amortization	(491,300)	(465,600)
Property and equipment, net	608,019	623,118
Land [Member]
Property and Equipment [Line Items]
Property and equipment	4,600	4,600
Building and Leasehold Improvements [Member]
Property and Equipment [Line Items]
Property and equipment	20,500	19,900
Machinery and Equipment [Member]
Property and Equipment [Line Items]
Property and equipment	931,900	926,100
Office Furniture and Equipment [Member]
Property and Equipment [Line Items]
Property and equipment	126,900	126,100
Construction in Progress [Member]
Property and Equipment [Line Items]
Property and equipment	$ 15,400	$ 12,000