Long-Term Debt (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Debt Disclosure [Line Items]
Senior secured revolving credit line	$ 267,100	$ 309,400
Total debt	274,199	317,335
Less: Current maturities of long-term debt	5,696	315,831
Long-term debt	268,503	1,504
Foreign
Debt Disclosure [Line Items]
Foreign loans	$ 7,099	$ 7,935