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DEBT AND CREDIT FACILITIES (Schedule Of Long-Term Debt) (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($) | Mar. 31, 2015 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt Instrument, Par Value |  | $ 3,448,200,000 |  | $ 3,980,000,000 |  |  |
Gain on extinguishment of debt |  | 392,900,000 |  | 16,200,000 |  | $ 0 |
Long-term Debt |  | 2,699,400,000 |  | 2,826,500,000 |  |  |
LONG-TERM DEBT |  | 2,699,400,000 |  | 2,826,500,000 |  |  |
Seven Hundred Million Four Point Eight Seven Five Two Thousand Twenty-one Senior Note [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt Instrument, Repurchased Face Amount |  | $ 10,700,000 |  | $ 10,000,000 |  |  | $ 58,300,000
Stated interest rate |  | 4.875% |  | 4.875% |  |  |
Debt Instrument, Par Value |  | $ 412,500,000 |  | $ 690,000,000 |  |  |
Debt Instrument, Unamortized Discount |  | $ 200,000 |  | $ 500,000 |  |  |
Debt Repurchase Discount |  | 50.00% |  | 40.50% |  |  | 52.00%
Gain on extinguishment of debt |  |  |  | $ 4,100,000 |  |  |
Type |  | Fixed |  | Fixed |  |  |
Final Maturity |  | 2021 |  | 2021 |  |  |
Long-term Debt | [1] | $ 410,600,000 |  | $ 686,000,000 |  |  |
Imputed interest rate |  | 4.89% |  | 4.89% |  |  |
Debt Instrument, Face Amount |  | $ 700,000,000 |  | $ 700,000,000 |  |  |
$500 million 4.80% 2020 Senior Notes [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt Instrument, Repurchased Face Amount |  | $ 1,800,000 |  | $ 10,000,000 |  |  | $ 43,800,000
Stated interest rate |  | 4.80% |  | 4.80% |  |  |
Debt Instrument, Par Value |  | $ 306,700,000 |  | $ 490,000,000 |  |  |
Debt Instrument, Unamortized Discount |  | $ 400,000 |  | $ 600,000 |  |  |
Debt Repurchase Discount |  | 50.00% |  | 40.25% |  |  | 54.30%
Gain on extinguishment of debt |  |  |  | $ 4,000,000 |  |  |
Type |  | Fixed |  | Fixed |  |  |
Final Maturity |  | 2020 |  | 2020 |  |  |
Long-term Debt | [2] | $ 305,200,000 |  | $ 487,200,000 |  |  |
Imputed interest rate |  | 4.83% |  | 4.83% |  |  |
Debt Instrument, Face Amount |  | $ 500,000,000.0 |  | $ 500,000,000 |  |  |
Discount Rate Used to Calculate Present Values of Remaining Scheduled Payments of Principal and Interest on Notes to Be Redeemed, Variable Rate Basis |  | treasury rate |  |  |  |  |
Discount Rate Used to Calculate Present Values of Remaining Scheduled Payments of Principal and Interest on Notes to Be Redeemed, Spread on Rate Basis |  | 0.35% |  |  |  |  |
$800 Million 6.25% 2040 Senior Notes [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt Instrument, Repurchased Face Amount |  |  |  |  |  |  | $ 45,900,000
Stated interest rate |  | 6.25% |  | 6.25% |  |  |
Debt Instrument, Par Value |  | $ 492,800,000 |  | $ 800,000,000 |  |  |
Debt Instrument, Unamortized Discount |  | $ 5,800,000 |  | $ 9,500,000 |  |  |
Debt Repurchase Discount |  |  |  |  |  |  | 52.50%
Type |  | Fixed |  | Fixed |  |  |
Final Maturity |  | 2040 |  | 2040 |  |  |
Long-term Debt | [3] | $ 482,700,000 |  | $ 783,300,000 |  |  |
Imputed interest rate |  | 6.34% |  | 6.34% |  |  |
Debt Instrument, Face Amount |  | $ 800,000,000 |  |  |  |  |
$400 Million 5.90% 2020 Senior Notes [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt Instrument, Repurchased Face Amount |  | $ 36,000,000 |  | $ 5,000,000 |  |  | $ 1,300,000
Stated interest rate |  | 5.90% |  | 5.90% |  |  |
Debt Instrument, Par Value |  | $ 290,800,000 |  | $ 395,000,000 |  |  |
Debt Instrument, Unamortized Discount |  | $ 800,000 |  | $ 1,300,000 |  |  |
Debt Repurchase Discount |  | 50.00% |  | 38.125% |  |  | 58.00%
Gain on extinguishment of debt |  | $ 1,900,000.0 |  |  |  |  |
Type |  | Fixed |  | Fixed |  |  |
Final Maturity |  | 2020 |  | 2020 |  |  |
Long-term Debt | [4] | $ 288,900,000 |  | $ 391,900,000 |  |  |
Imputed interest rate |  | 5.98% |  | 5.98% |  |  |
Debt Instrument, Face Amount |  | $ 400,000,000 |  | $ 400,000,000 |  |  |
$500 Million 3.95% 2018 Senior Notes [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt Instrument, Repurchased Face Amount |  | $ 20,000,000 |  |  |  |  | $ 44,000,000
Stated interest rate |  | 3.95% |  | 3.95% |  |  |
Debt Instrument, Par Value |  | $ 311,200,000 |  | $ 480,000,000 |  |  |
Debt Instrument, Unamortized Discount |  | $ 1,200,000 |  | $ 2,600,000 |  |  |
Debt Repurchase Discount |  |  |  | 30.875% |  |  | 77.50%
Gain on extinguishment of debt |  |  |  | $ 6,200,000 |  |  |
Type |  | Fixed |  | Fixed |  |  |
Final Maturity |  | 2018 |  | 2018 |  |  |
Long-term Debt | [5] | $ 309,100,000 |  | $ 475,300,000 |  |  |
Imputed interest rate |  | 6.30% |  | 5.17% |  |  |
Debt Instrument, Face Amount |  | $ 500,000,000 |  | $ 500,000,000.0 |  |  |
Five hundred forty million Eight point two five Twenty twenty First Lien Notes [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Stated interest rate |  | 8.25% |  |  |  |  |
Debt Instrument, Par Value |  | $ 540,000,000 |  |  |  |  |
Debt Instrument, Unamortized Discount |  | $ 32,100,000.0 |  |  |  |  |
Type |  | Fixed |  |  |  |  |
Final Maturity |  | 2020 |  |  |  |  |
Long-term Debt | [6] | $ 497,400,000 |  |  |  |  |
Imputed interest rate |  | 9.97% |  |  |  |  |
Debt Instrument, Face Amount |  | $ 540,000,000 |  | 0 |  |  |
Five hundred Forty-four Million Seven Point Seven Five Twenty Twenty Second Lien Notes [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Stated interest rate |  | 7.75% |  |  |  |  |
Debt Instrument, Par Value |  | $ 544,200,000 |  |  |  |  |
Debt Instrument, Unamortized Discount |  | $ 131,500,000 |  |  |  |  | $ 147,000,000
Type |  | Fixed |  |  |  |  |
Final Maturity |  | 2020 |  |  |  |  |
Long-term Debt | [7] | $ 403,200,000 |  |  |  |  |
Imputed interest rate |  | 15.55% |  |  |  |  |
Debt Instrument, Face Amount |  | $ 544,200,000 |  | 0 |  |  |
Revolving Credit Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt Instrument, Par Value |  | $ 550,000,000 |  | $ 1,125,000,000 |  |  |
Type |  | Variable |  | Variable |  |  |
Final Maturity |  | 2020 |  | 2017 |  |  |
Credit facility, amount outstanding |  | $ 0 | [8] | $ 0 | [9] |  |
Imputed interest rate |  |  |  | 2.94% |  |  |
Credit facility remaining capacity |  | 179,200,000 |  | $ 975,500,000 |  |  |
Letter of Credit [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Credit facility, amount outstanding |  | 186,300,000 |  | 149,500,000 |  |  |
Interest Rate Swap [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Fair Value Adjustment to Interest Rate Hedge |  | $ 2,300,000 |  | $ 2,800,000 |  |  |
Senior Notes Five Hundred Million [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Discount Rate Used to Calculate Present Values of Remaining Scheduled Payments of Principal and Interest on Notes to Be Redeemed, Variable Rate Basis |  | treasury rate |  |  |  |  |
Discount Rate Used to Calculate Present Values of Remaining Scheduled Payments of Principal and Interest on Notes to Be Redeemed, Spread on Rate Basis |  | 0.50% |  |  |  |  |
Senior Notes10 Year Tranche [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Discount Rate Used to Calculate Present Values of Remaining Scheduled Payments of Principal and Interest on Notes to Be Redeemed, Variable Rate Basis |  | treasury rate |  |  |  |  |
Discount Rate Used to Calculate Present Values of Remaining Scheduled Payments of Principal and Interest on Notes to Be Redeemed, Spread on Rate Basis |  | 0.25% |  |  |  |  |
Senior Notes30 Year Tranche [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt Instrument, Face Amount |  | $ 300,000,000 |  |  |  |  |
Discount Rate Used to Calculate Present Values of Remaining Scheduled Payments of Principal and Interest on Notes to Be Redeemed, Variable Rate Basis |  | treasury rate |  |  |  |  |
Discount Rate Used to Calculate Present Values of Remaining Scheduled Payments of Principal and Interest on Notes to Be Redeemed, Spread on Rate Basis |  | 0.40% |  |  |  |  |
Five Hundred Million Six Point Two Five Percent Two Thousand And Forty [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt Instrument, Face Amount |  | $ 500,000,000 |  |  |  |  |
Discount Rate Used to Calculate Present Values of Remaining Scheduled Payments of Principal and Interest on Notes to Be Redeemed, Variable Rate Basis |  | treasury rate |  |  |  |  |
Discount Rate Used to Calculate Present Values of Remaining Scheduled Payments of Principal and Interest on Notes to Be Redeemed, Spread on Rate Basis |  | 0.40% |  |  |  |  |
Minimum [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Base Rate |  | 0.005 |  |  |  |  |
[1] | During the third quarter of 2015, we purchased $10.7 million of outstanding 4.875 percent senior notes that were trading at 50.0 percent of par which resulted in a gain on extinguishment of $5.3 million. In addition, during the first quarter of 2015, we purchased $58.3 million of outstanding 4.875 percent senior notes that were trading at 52.0 percent of par, which resulted in a gain on extinguishment of $20.0 million. Also during the first quarter, 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. During the fourth quarter of 2014, we purchased $10.0 million of outstanding 4.875 percent senior notes that were trading at a discount of 40.5 percent which resulted in a gain on the extinguishment of debt of $4.1 million. As of December 31, 2015, the $700.0 million 4.875 percent senior notes were recorded at a par value of $412.5 million less debt issuance costs of $1.7 million and unamortized discounts of $0.2 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 debt issuance costs of $3.5 million and unamortized discounts of $0.5 million, based on an imputed interest rate of 4.89 percent.
[2] | During the third quarter of 2015, we purchased $1.8 million of outstanding 4.80 percent senior notes that were trading at 50.0 percent of par, which resulted in a gain on extinguishment of $0.9 million. In addition, during the first quarter of 2015, we purchased $43.8 million of outstanding 4.80 percent senior notes that were trading at 54.3 percent of par, which resulted in a gain on extinguishment of $15.6 million. Also during the first quarter, 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. During the fourth quarter of 2014, we purchased $10.0 million of outstanding 4.80 percent senior notes that were trading at a discount of 40.25 percent which resulted in a gain on the extinguishment of debt of $4.0 million. As of December 31, 2015, the $500.0 million 4.80 percent senior notes were recorded at a par value of $306.7 million less debt issuance costs of $1.1 million and 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 debt issuance costs of $2.2 million and 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 52.5 percent of par, which resulted in a gain on extinguishment of $15.0 million. Also during the first quarter, 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 December 31, 2015, the $800.0 million 6.25 percent senior notes were recorded at par value of $492.8 million less debt issuance costs of $4.3 million and unamortized discounts of $5.8 million, based on an imputed interest rate of 6.34 percent. As of December 31, 2014, the $800.0 million 6.25 percent senior notes were recorded at par value of $800.0 million less debt issuance costs of $7.2 million and unamortized discounts of $9.5 million, based on an imputed interest rate of 6.34 percent.
[4] | During the third quarter of 2015, we purchased $36.0 million of outstanding 5.90 percent senior notes that were trading at 50.0 percent of par, which resulted in a gain on extinguishment of $18.0 million. In addition, during the first quarter of 2015, we purchased $1.3 million of outstanding 5.90 percent senior notes that were trading at 58.0 percent of par, which resulted in a gain on extinguishment of $0.3 million. Also during the first quarter, 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. During the fourth quarter of 2014, we purchased $5.0 million of outstanding 5.90 percent senior notes that were trading at a discount of 38.125 percent which resulted in a gain on the extinguishment of debt of $1.9 million. As of December 31, 2015, the $400.0 million 5.90 percent senior notes were recorded at a par value of $290.8 million less debt issuance costs of $1.1 million and unamortized discounts of $0.8 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 debt issuance costs of $1.8 million and unamortized discounts of $1.3 million, based on an imputed interest rate of 5.98 percent.
[5] | During the third quarter, on August 28, 2015, we purchased for cash as part of a tender offer, $124.8 million of the 3.95 percent senior notes for $68.6 million, resulting in a gain on extinguishment of $54.9 million, net of amounts expensed for reacquisition costs, unamortized original issue discount and deferred origination fees. In addition, during the first quarter of 2015, we purchased $44.0 million of outstanding 3.95 percent senior notes that were trading at 77.5 percent of par, which resulted in a gain on the extinguishment of debt of $7.1 million.During the fourth quarter of 2014, we purchased $20.0 million of outstanding 3.95 percent senior notes that were trading at a discount of 30.875 percent which resulted in a gain on the extinguishment of debt of $6.2 million. As of December 31, 2015, the $500.0 million 3.95 percent senior notes were recorded at a par value of $311.2 million less debt issuance cost of $0.9 million and unamortized discounts of $1.2 million, based on an imputed interest rate of 6.30 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 debt issuance costs of $2.1 million and unamortized discounts of $2.6 million, based on an imputed interest rate of 5.17 percent.
[6] | As of December 31, 2015, the $540.0 million 8.25 percent first lien notes were recorded at a par value of $540.0 million less debt issuance costs of $10.5 million and unamortized discounts of $32.1 million, based on an imputed interest rate of 9.97 percent.
[7] | As of December 31, 2015, the $544.2 million 7.75 percent second lien notes were recorded at a par value of $544.2 million less debt issuance costs of $9.5 million and unamortized discounts of $131.5 million, based on an imputed interest rate of 15.55 percent. See NOTE 6 - FAIR VALUE OF FINANCIAL INSTRUMENTS for further discussion of unamortized discount as a result of the exchange offers.
[8] | As of December 31, 2015, no loans were drawn under the $550.0 million ABL Facility and we had total availability of $366.0 million as a result of borrowing base limitations. As of December 31, 2015, the principal amount of letter of credit obligations totaled $186.3 million and commodity hedge obligations totaled $0.5 million, thereby further reducing available borrowing capacity on our ABL Facility to $179.2 million.
[9] | As of December 31, 2014, we had no revolving loans drawn under the revolving credit agreement, which had total availability of $1.125 billion as of December 31, 2014. As of December 31, 2014, the principal amount of letter of credit obligations totaled $149.5 million, thereby reducing available borrowing capacity to $975.5 million.

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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20, 22 -Article 5 + Details
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- Definition Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 + Details
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- Definition Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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