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DEBT AND CREDIT FACILITIES (Schedule Of Long-Term Debt) (Details) - USD ($) | 3 Months Ended | 6 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 30, 2015 | Jun. 30, 2014 | Jun. 30, 2015 | Jun. 30, 2014 | Dec. 31, 2013 | Mar. 31, 2015 | Mar. 30, 2015 | Dec. 31, 2014
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment of debt |  | $ 0 |  | $ 0 | $ 313,700,000 |  | $ 0 |  |  |  |  |
Total Face Amount |  | 3,621,500,000 |  |  | 3,621,500,000 |  |  |  |  |  | $ 3,980,000,000 |
Letters of credit outstanding |  | 198,000,000 |  |  | 198,000,000 |  |  |  |  |  | 149,500,000 |
Long-term Debt |  | 2,887,400,000 |  |  | 2,887,400,000 |  |  |  |  |  | 2,843,300,000 |
Current portion of long-term debt |  | 0 |  |  | 0 |  |  |  |  |  | 0 |
Long-term debt noncurrent portion |  | 2,887,400,000 |  |  | 2,887,400,000 |  |  |  |  |  | $ 2,843,300,000 |
$700 Million 4.875% 2021 Senior Note [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Repurchased Face Amount |  | $ 58,300,000 |  |  | $ 58,300,000 |  |  |  |  |  |  |
Stated interest rate |  | 4.875% |  |  | 4.875% |  |  |  |  |  | 4.875% |
Debt Repurchase Discount |  | 52.00% |  |  | 52.00% |  |  |  |  |  |  |
Debt Instrument, Face Amount Exchanged |  | $ 208,500,000 |  |  | $ 208,500,000 |  |  |  |  |  |  |
Type |  |  |  |  | Fixed |  |  | Fixed |  |  |  |
Final Maturity |  |  |  |  | 2021 |  |  | 2021 |  |  |  |
Total Face Amount |  | 700,000,000 |  |  | $ 700,000,000 |  |  |  |  |  | $ 700,000,000 |
Debt Instrument, Par Value |  | 423,200,000 |  |  | 423,200,000 |  |  |  |  |  | 690,000,000 |
Long-term Debt | [1] | 422,900,000 |  |  | 422,900,000 |  |  |  |  |  | 689,500,000 |
Debt Instrument, Unamortized Discount |  | $ 300,000 |  |  | $ 300,000 |  |  |  |  |  | $ 500,000 |
Imputed interest rate |  | 4.89% |  |  | 4.89% |  |  |  |  |  | 4.88% |
$500 million 4.80% 2020 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Repurchased Face Amount |  | $ 43,800,000 |  |  | $ 43,800,000 |  |  |  |  |  |  |
Stated interest rate |  | 4.80% |  |  | 4.80% |  |  |  |  |  | 4.80% |
Debt Repurchase Discount |  | 54.30% |  |  | 54.30% |  |  |  |  |  |  |
Debt Instrument, Face Amount Exchanged |  | $ 137,800,000 |  |  | $ 137,800,000 |  |  |  |  |  |  |
Type |  |  |  |  | Fixed |  |  | Fixed |  |  |  |
Final Maturity |  |  |  |  | 2020 |  |  | 2020 |  |  |  |
Total Face Amount |  | 500,000,000 |  |  | $ 500,000,000 |  |  |  |  |  | $ 500,000,000 |
Debt Instrument, Par Value |  | 308,500,000 |  |  | 308,500,000 |  |  |  |  |  | 490,000,000 |
Long-term Debt | [2] | 308,100,000 |  |  | 308,100,000 |  |  |  |  |  | 489,400,000 |
Debt Instrument, Unamortized Discount |  | $ 400,000 |  |  | $ 400,000 |  |  |  |  |  | $ 600,000 |
Imputed interest rate |  | 4.83% |  |  | 4.83% |  |  |  |  |  | 4.83% |
$800 Million 6.25% 2040 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Repurchased Face Amount |  | $ 45,900,000 |  |  | $ 45,900,000 |  |  |  |  |  |  |
Stated interest rate |  | 6.25% |  |  | 6.25% |  |  |  |  |  |  |
Debt Repurchase Discount |  | 52.50% |  |  | 52.50% |  |  |  |  |  |  |
Debt Instrument, Face Amount Exchanged |  | $ 261,300,000 |  |  | $ 261,300,000 |  |  |  |  |  |  |
Type |  |  |  |  | Fixed |  |  | Fixed |  |  |  |
Final Maturity |  |  |  |  | 2040 |  |  | 2040 |  |  |  |
Total Face Amount |  | 800,000,000 |  |  | $ 800,000,000 |  |  |  |  |  |  |
Debt Instrument, Par Value |  | 492,800,000 |  |  | 492,800,000 |  |  |  |  |  | $ 800,000,000 |
Long-term Debt | [3] | 487,000,000 |  |  | 487,000,000 |  |  |  |  |  | 790,500,000 |
Debt Instrument, Unamortized Discount |  | $ 5,800,000 |  |  | $ 5,800,000 |  |  |  |  |  | $ 9,500,000 |
Imputed interest rate |  | 6.34% |  |  | 6.34% |  |  |  |  |  | 6.34% |
$400 Million 5.90% 2020 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Repurchased Face Amount |  | $ 1,300,000 |  |  | $ 1,300,000 |  |  |  |  |  |  |
Stated interest rate |  | 5.90% |  |  | 5.90% |  |  |  |  |  | 5.90% |
Debt Repurchase Discount |  | 58.00% |  |  | 58.00% |  |  |  |  |  |  |
Debt Instrument, Face Amount Exchanged |  | $ 67,000,000 |  |  | $ 67,000,000 |  |  |  |  |  |  |
Type |  |  |  |  | Fixed |  |  | Fixed |  |  |  |
Final Maturity |  |  |  |  | 2020 |  |  | 2020 |  |  |  |
Total Face Amount |  | 400,000,000 |  |  | $ 400,000,000 |  |  |  |  |  | $ 400,000,000 |
Debt Instrument, Par Value |  | 326,800,000 |  |  | 326,800,000 |  |  |  |  |  | 395,000,000 |
Long-term Debt | [4] | 325,800,000 |  |  | 325,800,000 |  |  |  |  |  | 393,700,000 |
Debt Instrument, Unamortized Discount |  | $ 1,000,000 |  |  | $ 1,000,000 |  |  |  |  |  | $ 1,300,000 |
Imputed interest rate |  | 5.98% |  |  | 5.98% |  |  |  |  |  | 5.98% |
$500 Million 3.95% 2018 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Repurchased Face Amount |  | $ 44,000,000 |  |  | $ 44,000,000 |  |  |  |  |  |  |
Stated interest rate |  | 3.95% |  |  | 3.95% |  |  |  |  |  | 3.95% |
Debt Repurchase Discount |  | 77.50% |  |  | 77.50% |  |  |  |  |  |  |
Type |  |  |  |  | Fixed |  |  | Fixed |  |  |  |
Final Maturity |  |  |  |  | 2018 |  |  | 2018 |  |  |  |
Total Face Amount |  | $ 500,000,000.0 |  |  | $ 500,000,000.0 |  |  |  |  |  | $ 500,000,000 |
Debt Instrument, Par Value |  | 436,000,000 |  |  | 436,000,000 |  |  |  |  |  | 480,000,000 |
Long-term Debt | [5] | 434,000,000 |  |  | 434,000,000 |  |  |  |  |  | 477,400,000 |
Debt Instrument, Unamortized Discount |  | $ 2,000,000 |  |  | $ 2,000,000 |  |  |  |  |  | $ 2,600,000 |
Imputed interest rate |  | 6.22% |  |  | 6.22% |  |  |  |  |  | 5.17% |
Five hundred forty million Eight point two five Twenty twenty First Lien Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stated interest rate |  | 8.25% |  |  | 8.25% |  |  |  |  |  |  |
Type |  |  |  |  | Fixed |  |  |  |  |  |  |
Final Maturity |  |  |  |  | 2020 |  |  |  |  |  |  |
Total Face Amount |  | $ 540,000,000 |  |  | $ 540,000,000 |  |  |  |  |  | $ 0 |
Debt Instrument, Par Value |  | 540,000,000 |  |  | 540,000,000 |  |  |  |  |  |  |
Long-term Debt |  | 504,900,000 |  |  | 504,900,000 |  |  |  |  |  |  |
Debt Instrument, Unamortized Discount |  | $ 35,051,000.000 |  |  | $ 35,051,000.000 |  |  |  |  |  |  |
Imputed interest rate |  | 9.97% |  |  | 9.97% |  |  |  |  |  |  |
Five hundred Forty-four Million Seven Point Seven Five Twenty Twenty Second Lien Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stated interest rate |  | 7.75% |  |  | 7.75% |  |  |  |  |  |  |
Discount Received in Debt Exchange of $400M 5.90% Notes |  | $ 15,500,000 |  |  | $ 15,500,000 |  |  |  |  |  |  |
Debt Instrument, Face Amount Received in Debt Exchange of $400M 5.90% Notes |  | 57,500,000 |  |  | 57,500,000 |  |  |  |  |  |  |
Debt Instrument, Face Amount Received in Debt Exchange of $800M 6.25% Notes |  | 203,500,000 |  |  | 203,500,000 |  |  |  |  |  |  |
Discount Received in Debt Exchange of $800M 6.25% Notes |  | 55,000,000 |  |  | 55,000,000 |  |  |  |  |  |  |
Discount Received in Debt Exchange of $500M 4.80% Notes |  | 30,500,000 |  |  | 30,500,000 |  |  |  |  |  |  |
Debt Instrument, Face Amount Received in Debt Exchange of $500M 4.80% Notes |  | 112,900,000 |  |  | 112,900,000 |  |  |  |  |  |  |
Discount Received in Debt Exchange of $700M 4.875% Notes |  | 46,000,000 |  |  | 46,000,000 |  |  |  |  |  |  |
Debt instrument, Face Amount Received in Debt Exchange of $700M 4.875% Notes |  | 170,300,000 |  |  | $ 170,300,000 |  |  |  |  |  |  |
Type |  |  |  |  | Fixed |  |  |  |  |  |  |
Final Maturity |  |  |  |  | 2020 |  |  |  |  |  |  |
Total Face Amount |  | 544,200,000 |  |  | $ 544,200,000 |  |  |  |  |  | $ 0 |
Debt Instrument, Par Value |  | 544,200,000 |  |  | 544,200,000 |  |  |  |  |  |  |
Long-term Debt |  | 402,200,000 |  |  | 402,200,000 |  |  |  |  |  |  |
Debt Instrument, Unamortized Discount |  | $ 142,000,000 |  |  | $ 142,000,000 |  |  |  | $ 147,000,000 |  |  |
Imputed interest rate |  | 15.55% |  |  | 15.55% |  |  |  |  |  | 15.55% |
Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Type |  |  |  |  | Variable |  |  | Variable |  |  |  |
Final Maturity |  |  |  |  | 2020 |  |  | 2017 |  |  |  |
Debt Instrument, Par Value |  | $ 550,000,000 |  |  | $ 550,000,000 |  |  |  |  | $ 900,000,000 | $ 1,125,000,000 |
Credit facility, amount outstanding |  | 0 | [6] |  | 0 | [6] |  |  |  |  | 0 | [7]
Revolving credit facility, borrowing capacity |  | 532,700,000 |  |  | 532,700,000 |  |  |  |  |  |  |
Letters of credit outstanding |  | 198,000,000 |  |  | 198,000,000 |  |  |  |  |  | $ 149,500,000 |
Foreign Exchange Hedge Obligations |  | $ 2,100,000 |  |  | $ 2,100,000 |  |  |  |  |  |  |
Imputed interest rate |  | 2.25% |  |  | 2.25% |  |  |  |  |  | 2.94% |
Credit facility remaining capacity |  | $ 332,600,000 |  |  | $ 332,600,000 |  |  |  |  |  | $ 975,500,000 |
Interest Rate Swap [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Fair Value Adjustment to Interest Rate Hedge |  | $ 2,500,000 |  |  | 2,500,000 |  |  |  |  |  | $ 2,800,000 |
Debt Repurchase [Member] | $700 Million 4.875% 2021 Senior Note [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment of debt |  |  |  |  | 20,000,000 |  |  |  |  |  |  |
Debt Repurchase [Member] | $500 million 4.80% 2020 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment of debt |  |  |  |  | 15,600,000 |  |  |  |  |  |  |
Debt Repurchase [Member] | $800 Million 6.25% 2040 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment of debt |  |  |  |  | 15,000,000 |  |  |  |  |  |  |
Debt Repurchase [Member] | $400 Million 5.90% 2020 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment of debt |  |  |  |  | 300,000 |  |  |  |  |  |  |
Debt Repurchase [Member] | $500 Million 3.95% 2018 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment of debt |  |  |  |  | 7,100,000 |  |  |  |  |  |  |
Exchange of Debt [Member] | $700 Million 4.875% 2021 Senior Note [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment of debt |  |  |  |  | 83,100,000 |  |  |  |  |  |  |
Exchange of Debt [Member] | $500 million 4.80% 2020 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment of debt |  |  |  |  | 54,600,000 |  |  |  |  |  |  |
Exchange of Debt [Member] | $800 Million 6.25% 2040 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment of debt |  |  |  |  | 107,300,000 |  |  |  |  |  |  |
Exchange of Debt [Member] | $400 Million 5.90% 2020 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Gain on extinguishment of debt |  |  |  |  | $ 24,500,000 |  |  |  |  |  |  |
[1] | During the first quarter of 2015, we purchased $58.3 million of outstanding 4.875 percent senior notes that were trading at a discount of 52.0 percent which resulted in a gain on extinguishment of $20.0 million. In addition, on March 27, 2015, we exchanged as part of a tender offer $208.5 million of the 4.875 percent senior notes for $170.3 million of the 7.75 percent second lien notes at a discount of $46.0 million based on an imputed interest rate of 15.55 percent, resulting in a gain on extinguishment of $83.1 million, net of amounts expensed for unamortized original issue discount and deferred origination fees. As of June 30, 2015, the $700.0 million 4.875 percent senior notes were recorded at a par value of $423.2 million less unamortized discounts of $0.3 million, based on an imputed interest rate of 4.89 percent. As of December 31, 2014, the $700.0 million 4.875 percent senior notes were recorded at a par value of $690.0 million less unamortized discounts of $0.5 million based on an imputed interest rate of 4.88 percent.
[2] | During the first quarter of 2015, we purchased $43.8 million of outstanding 4.80 percent senior notes that were trading at a discount of 54.3 percent, which resulted in a gain on extinguishment of $15.6 million. In addition, on March 27, 2015, we exchanged as part of a tender offer $137.8 million of the 4.80 percent senior notes for $112.9 million of the 7.75 percent second lien notes at a discount of $30.5 million based on an imputed interest rate of 15.55 percent, resulting in a gain on extinguishment of $54.6 million, net of amounts expensed for unamortized original issue discount and deferred origination fees. As of June 30, 2015, the $500.0 million 4.80 percent senior notes were recorded at a par value of $308.5 million less unamortized discounts of $0.4 million, based on an imputed interest rate of 4.83 percent. As of December 31, 2014, the $500.0 million 4.80 percent senior notes were recorded at a par value of $490.0 million less unamortized discounts of $0.6 million based on an imputed interest rate of 4.83 percent.
[3] | During the first quarter of 2015, we purchased $45.9 million of outstanding 6.25 percent senior notes that were trading at a discount of 52.5 percent, which resulted in a gain on extinguishment of $15.0 million. In addition, on March 27, 2015, we exchanged as part of a tender offer $261.3 million of the 6.25 percent senior notes for $203.5 million of the 7.75 percent second lien notes at a discount of $55.0 million based on an imputed interest rate of 15.55 percent, resulting in a gain on extinguishment of $107.3 million, net of amounts expensed for unamortized original issue discount and deferred origination fees. As of June 30, 2015, the $800 million 6.25 percent senior notes were recorded at a par value of $492.8 million less unamortized discounts of $5.8 million, based on an imputed interest rate of 6.34 percent. As of December 31, 2014, the $800 million 6.25 percent senior notes were recorded at a par value of $800.0 million less unamortized discounts of $9.5 million based on an imputed interest rate of 6.34 percent.
[4] | During the first quarter of 2015, we purchased $1.3 million of outstanding 5.90 percent senior notes that were trading at a discount of 58.0 percent, which resulted in a gain on extinguishment of $0.3 million. In addition, on March 27, 2015, we exchanged as part of a tender offer $67.0 million of the 5.90 percent senior notes for $57.5 million of the 7.75 percent second lien notes at a discount of $15.5 million based on an imputed interest rate of 15.55 percent, resulting in a gain on extinguishment of $24.5 million, net of amounts expensed for unamortized original issue discount and deferred origination fees. As of June 30, 2015, the $400.0 million 5.90 percent senior notes were recorded at a par value of $326.8 million less unamortized discounts of $1.0 million, based on an imputed interest rate of 5.98 percent. As of December 31, 2014, the $400.0 million 5.90 percent senior notes were recorded at a par value of $395.0 million less unamortized discounts of $1.3 million based on an imputed interest rate of 5.98 percent.
[5] | During the first quarter of 2015, we purchased $44.0 million of outstanding 3.95 percent senior notes that were trading at a discount of 77.5 percent, which resulted in a gain on the extinguishment of debt of $7.1 million. As of June 30, 2015, the $500.0 million 3.95 percent senior notes were recorded at a par value of $436.0 million less unamortized discounts of $2.0 million, based on an imputed interest rate of 6.22 percent. As of December 31, 2014, the $500.0 million 3.95 percent senior notes were recorded at a par value of $480.0 million less unamortized discounts of $2.6 million based on an imputed interest rate of 5.17 percent.
[6] | As of June 30, 2015, no loans were drawn under the ABL Facility and we had total availability of $532.7 million as a result of borrowing base limitations. As of June 30, 2015, the principal amount of letter of credit obligations totaled $198.0 million and foreign exchange hedge obligations totaled $2.1 million, thereby further reducing available borrowing capacity on our ABL Facility to $332.6 million.
[7] | As of December 31, 2014, we had no revolving loans drawn under the revolving credit agreement which had $1.125 billion availability. As of December 31, 2014, the principal amount of letter of credit obligations totaled $149.5 million, thereby further reducing available borrowing capacity on the revolving credit agreement to $975.5 million.

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