DEBT (Summary of Debt Additional Information) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 6.30% notes due 2013	Jun. 30, 2013 6.30% notes due 2013	Dec. 31, 2012 6.30% notes due 2013	Jun. 30, 2011 6.30% notes due 2013	Jun. 30, 2008 6.30% notes due 2013	Dec. 31, 2013 10.125% notes due 2015	Dec. 31, 2012 10.125% notes due 2015	Feb. 28, 2009 10.125% notes due 2015	Dec. 31, 2013 6.50% notes due 2016	Dec. 31, 2012 6.50% notes due 2016	Jun. 30, 2011 6.50% notes due 2016	Dec. 31, 2013 6.40% notes due 2017	Dec. 31, 2012 6.40% notes due 2017	Dec. 31, 2007 6.40% notes due 2017	Dec. 31, 2013 7.00% notes due 2018	Dec. 31, 2012 7.00% notes due 2018	Jun. 30, 2008 7.00% notes due 2018	Dec. 31, 2013 10.375% notes due 2018	Dec. 31, 2012 10.375% notes due 2018	Feb. 28, 2009 10.375% notes due 2018	Dec. 31, 2013 7.50% notes due 2021	Dec. 31, 2012 7.50% notes due 2021	Jun. 30, 2011 7.50% notes due 2021	Dec. 31, 2013 7.15% notes due 2037	Dec. 31, 2012 7.15% notes due 2037	Dec. 31, 2007 7.15% notes due 2037
Debt Instrument [Line Items]
Interest rate	5.60%	6.50%	6.30%	6.30%	6.30%	6.30%	6.30%	10.125%	10.125%	10.125%	6.50%	6.50%	6.50%	6.40%	6.40%	6.40%	7.00%	7.00%	7.00%	10.375%	10.375%	10.375%	7.50%	7.50%	7.50%	7.15%	7.15%	7.15%
Maturity year			2013		2013	2013	2013	2015	2015	2015	2016	2016	2016	2017	2017	2017	2018	2018	2018	2018	2018	2018	2021	2021	2021	2037	2037	2037
Decrease in unamortized discounts					$ 30			$ 185	$ 265					$ 93	$ 112		$ 228	$ 269		$ 1,157	$ 1,324					$ 627	$ 635
Effective interest rate								9.59%	9.59%		6.02%	6.02%		7.41%	7.41%		7.87%	7.87%		10.62%	10.62%		7.75%	7.75%		8.05%	8.05%
Increase in unamortized deferred gain realized								$ 2,082	$ 2,983		$ 11,627	$ 15,060