LOSS ON EXTINGUISHMENT OF DEBT (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended							3 Months Ended	12 Months Ended		12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 5.375% Convertible Notes due in August, 2014	Dec. 31, 2011 5.375% Convertible Notes due in August, 2014	Dec. 31, 2010 5.375% Convertible Notes due in August, 2014	Jun. 30, 2009 5.375% Convertible Notes due in August, 2014	Jun. 30, 2011 4.00% Convertible Notes due in November, 2013	Dec. 31, 2011 4.00% Convertible Notes due in November, 2013	Dec. 31, 2010 4.00% Convertible Notes due in November, 2013	Dec. 31, 2010 Cash settlement of written call options	Dec. 31, 2012 Term Loan B Facility	Dec. 31, 2010 Term Loan B Facility	Dec. 31, 2011 Senior Notes	Dec. 31, 2011 Senior Secured Term Loan Facility
Long-term debt
Total (gain) loss on extinguishment of debt	$ 20,080	$ 36,844	$ 32,413	$ 2,455	$ 31,629	$ 20,652		$ 4,700	$ 4,708		$ 10,064	$ 17,625	$ 1,697	$ (148)	$ 655
Interest rate on debt (as a percent)				5.375%	5.375%	5.375%	5.375%		4.00%	4.00%