INTEREST EXPENSE Schedule of extinguishment of debt (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Extinguishment of Debt [Line Items]
Net (gain) / loss on extinguishment of debt	$ (448)	$ 3,424	$ (448)	$ 24,979
Refinance of 2013 Convertible Notes [Member]
Extinguishment of Debt [Line Items]
Net (gain) / loss on extinguishment of debt	3,763	3,424	3,763	22,591
Floating Rate Notes [Member]
Extinguishment of Debt [Line Items]
Net (gain) / loss on extinguishment of debt	(4,211)	0	(4,211)	0
2016 Fixed Rate Notes [Member]
Extinguishment of Debt [Line Items]
Net (gain) / loss on extinguishment of debt	$ 0	$ 0	$ 0	$ 2,388