DEBT (7 1/2% Senior Notes Due 2020) (Details) (USD $)	9 Months Ended							0 Months Ended			9 Months Ended					1 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Sep. 30, 2012 8 1/2% Senior Notes due 2014		Dec. 31, 2011 8 1/2% Senior Notes due 2014		Sep. 17, 2012 7 1/2% Senior Notes due 2020	Sep. 30, 2012 7 1/2% Senior Notes due 2020	Dec. 31, 2011 7 1/2% Senior Notes due 2020	Sep. 30, 2012 On or after September 15 2016 7 1/2% Senior Notes due 2020	Sep. 30, 2012 On or after September 15 2017 7 1/2% Senior Notes due 2020	Sep. 30, 2012 On or after September 15 2018 and thereafter 7 1/2% Senior Notes due 2020	Sep. 30, 2012 Prior to September 15 2016 7 1/2% Senior Notes due 2020	Sep. 30, 2012 Prior To September 15 2015 7 1/2% Senior Notes due 2020	Oct. 29, 2012 Subsequent Event 8 1/2% Senior Notes due 2014
Debt
Interest rate (as a percent)				8.50%		8.50%			7.50%	7.50%
Debt, Principal	$ 2,100,012,000		$ 1,705,012,000	$ 600,000,000	[1]	$ 600,000,000	[1]	$ 500,000,000	$ 500,000,000	$ 0
Proceeds from Issuance of Senior Long-term Debt	491,250,000	0						491,250,000
Redeemed Principal Amount of Senior Notes																$ 300,000,000
Redemption Price As Percentage Of Principal Amount (as a percent)											103.75%	101.88%	100.00%		107.50%	110.24%
Debt Instruments Basis Spread Early Redemption														0.50%
Percentage Of Senior Notes That May Be Redeemed With Proceeds From Certain Equity Offerings															35.00%
Percentage of Senior Notes That Must Remain Outstanding															65.00%
Number of days the redemption of senior notes must occur within from the date of the equity offering															120 days

[1] In September 2012, the Company irrevocably called $300.0 million (50% of the aggregate principal amount) of the 8½% senior notes due 2014 and redeemed those called notes in October 2012 at 110.24% of par, recognizing a loss of $36.3 million upon redemption.