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DEBT AND CREDIT FACILITIES (Schedule Of Long-Term Debt) (Details) - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2016 | Dec. 31, 2015
Debt Instrument [Line Items] |  |  |  |
Total Face Amount |  | $ 3,131.7 |  | $ 3,448.2
Letters of credit outstanding |  | 112.8 |  | 186.3
Long-term Debt |  | 2,489.7 |  | 2,699.4
Debt, Long-term and Short-term, Combined Amount |  | 2,507.2 |  |
Long-term Debt, Current Maturities |  | $ 17.5 |  |
$700 Million 4.875% 2021 Senior Note [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate |  | 4.875% |  |
Debt Instrument, Face Amount Exchanged |  | $ 76.3 |  |
Total Face Amount |  | 336.2 | [1],[2],[3],[4],[5],[6],[7],[8],[9] | 412.5
Unamortized Debt Issuance Expense |  | (1.3) | [1],[2],[3],[4],[5],[6],[7],[8],[9] | (1.7)
Long-term Debt |  | 334.7 | [1],[2],[3],[4],[5],[6],[7],[8],[9] | 410.6
Debt Instrument, Unamortized Discount |  | $ (0.2) | [1],[2],[3],[4],[5],[6],[7],[8],[9] | $ (0.2)
Imputed interest rate |  | 4.89% | [1],[2],[3],[4],[5],[6],[7],[8],[9] | 4.89%
$500 million 4.80% 2020 Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate |  | 4.80% |  |
Debt Instrument, Face Amount Exchanged |  | $ 44.7 |  |
Total Face Amount |  | 249.3 |  | $ 306.7
Unamortized Debt Issuance Expense |  | (0.8) |  | (1.1)
Long-term Debt |  | 248.3 |  | 305.2
Debt Instrument, Unamortized Discount |  | $ (0.2) |  | $ (0.4)
Imputed interest rate |  | 4.83% |  | 4.83%
$800 Million 6.25% 2040 Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate |  | 6.25% |  |
Debt Instrument, Face Amount Exchanged |  | $ 194.4 |  |
Total Face Amount |  | 298.4 |  | $ 492.8
Unamortized Debt Issuance Expense |  | (2.5) |  | (4.3)
Long-term Debt |  | 292.4 |  | 482.7
Debt Instrument, Unamortized Discount |  | $ (3.5) |  | $ (5.8)
Imputed interest rate |  | 6.34% |  | 6.34%
$400 Million 5.90% 2020 Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate |  | 5.90% |  |
Debt Instrument, Face Amount Exchanged |  | $ 65.1 |  |
Total Face Amount |  | 225.6 |  | $ 290.8
Unamortized Debt Issuance Expense |  | (0.7) |  | (1.1)
Long-term Debt |  | 224.3 |  | 288.9
Debt Instrument, Unamortized Discount |  | $ (0.6) |  | $ (0.8)
Imputed interest rate |  | 5.98% |  | 5.98%
$500 Million 3.95% 2018 Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate |  | 3.95% |  |
Debt Instrument, Face Amount Exchanged |  | $ 17.6 |  |
Total Face Amount |  | 283.6 |  | $ 311.2
Unamortized Debt Issuance Expense |  | (0.6) |  | (0.9)
Long-term Debt |  | 282.2 |  | 309.1
Debt Instrument, Unamortized Discount |  | $ (0.8) |  | $ (1.2)
Imputed interest rate |  | 6.15% |  | 6.30%
Five hundred forty million Eight point two five Twenty twenty First Lien Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate |  | 8.25% |  |
Total Face Amount |  | $ 540.0 |  | $ 540.0
Unamortized Debt Issuance Expense |  | (9.2) |  | (10.5)
Long-term Debt |  | 501.8 |  | 497.4
Debt Instrument, Unamortized Discount |  | $ (29.0) |  | $ (32.1)
Imputed interest rate |  | 9.97% |  | 9.97%
Two hundred Eighteen Point Five Million Eight Point Zero Twenty Twenty One Point Five Lien Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Stated interest rate |  | 8.00% |  |
Debt Instrument, Carrying Amount Received in Debt Exchange of $544.2M 7.75% Notes |  | $ 76.3 |  |
Debt Instrument, Face Amount Received in Debt Exchange of $544M 7.75% Notes |  | 57.0 |  |
Debt Instrument, Face Amount Received in Debt Exchange of $500M 3.95% Notes |  | 11.4 |  |
Debt Instrument, Carrying Amount Received in Debt Exchange of $500M 3.95% Notes |  | 15.3 |  |
Debt Instrument, Carrying Amount Received in Debt Exchange of $400M 5.90% Notes |  | 34.9 |  |
Debt Instrument, Carrying Value Received in Debt Exchange of $800M 6.25% Notes |  | 101.5 |  |
Debt Instrument, Carrying Value Received in Debt Exchange of $500M 4.80% Notes |  | 23.9 |  |
Debt instrument, Carrying Value Received in Debt Exchange of $700M 4.875% Notes |  | 40.9 |  |
Debt Instrument, Face Amount Received in Debt Exchange of $400M 5.90% Notes |  | 26.0 |  |
Debt Instrument, Face Amount Received in Debt Exchange of $800M 6.25% Notes |  | 75.8 |  |
Debt Instrument, Face Amount Received in Debt Exchange of $500M 4.80% Notes |  | 17.9 |  |
Debt instrument, Face Amount Received in Debt Exchange of $700M 4.875% Notes |  | 30.5 |  |
Total Face Amount |  | 218.5 |  |
Debt Instrument, Par Value |  | 218.5 |  |
Unamortized Debt Issuance Expense |  | 0.0 |  |
Undiscounted interest |  | 74.3 |  |
Long-term Debt |  | $ 292.8 |  |
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, Face Amount Exchanged |  | $ 114.1 |  |
Total Face Amount |  | 430.1 |  | $ 544.2
Unamortized Debt Issuance Expense |  | (6.6) |  | (9.5)
Long-term Debt |  | 328.6 |  | 403.2
Debt Instrument, Unamortized Discount |  | $ (94.9) |  | $ (131.5)
Imputed interest rate |  | 15.55% |  | 15.55%
Revolving Credit Facility [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Par Value |  | $ 550.0 |  | $ 550.0
Credit facility, amount outstanding | [2] | 0.0 |  |
Line of Credit Facility, Maximum Borrowing Capacity |  | 425.6 |  | 366.0
Letters of credit outstanding |  | 112.8 |  |
Credit facility remaining capacity |  | 312.8 |  | 179.2
Letter of Credit [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Credit facility, amount outstanding |  |  |  | 186.3
Hedge Obligations [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Credit facility, amount outstanding |  |  |  | 0.5
Interest Rate Swap [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Fair Value Adjustment to Interest Rate Hedge |  | $ 2.1 |  | $ 2.3
[1] | As of December 31, 2015, no loans were drawn under the 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.
[2] | As of June 30, 2016, no loans were drawn under the ABL Facility and we had total availability of $425.6 million as a result of borrowing base limitations. As of June 30, 2016, the principal amount of letter of credit obligations totaled $112.8 million, thereby further reducing available borrowing capacity on our ABL Facility to $312.8 million.
[3] | On March 2, 2016, we exchanged as part of an exchange offer $114.1 million of the 7.75 percent senior notes for $57.0 million of the 8.00 percent 1.5 lien notes that are recorded at a carrying value of $76.3 million, including undiscounted interest payments as of June 30, 2016.
[4] | On March 2, 2016, we exchanged as part of an exchange offer $17.6 million of the 3.95 percent senior notes for $11.4 million of the 8.00 percent 1.5 lien notes that are recorded at a carrying value of $15.3 million, including undiscounted interest payments as of June 30, 2016. Additionally, during the first quarter of 2016 we entered into a debt for equity exchange; see NOTE 15 - CAPITAL STOCK for further discussion of this transaction.
[5] | On March 2, 2016, we exchanged as part of an exchange offer $194.4 million of the 6.25 percent senior notes for $75.8 million of the 8.00 percent 1.5 lien notes that are recorded at a carrying value of $101.5 million, including undiscounted interest payments as of June 30, 2016.
[6] | On March 2, 2016, we exchanged as part of an exchange offer $44.7 million of the 4.80 percent senior notes for $17.9 million of the 8.00 percent 1.5 lien notes that are recorded at a carrying value of $23.9 million, including undiscounted interest payments as of June 30, 2016. Additionally, during the second quarter of 2016 we entered into a debt for equity exchange; see NOTE 15 - CAPITAL STOCK for further discussion of this transaction.
[7] | On March 2, 2016, we exchanged as part of an exchange offer $65.1 million of the 5.90 percent senior notes for $26.0 million of the 8.00 percent 1.5 lien notes that are recorded at a carrying value of $34.9 million, including undiscounted interest payments as of June 30, 2016.
[8] | See the section entitled "$218.5 million 8.00 percent 2020 Senior Secured 1.5 Lien Notes - 2016 Exchange Offers" below for further discussion related to this instrument.
[9] | n March 2, 2016, we exchanged as part of an exchange offer $76.3 million of the 4.875 percent senior notes for $30.5 million of the 8.00 percent 1.5 lien notes that are recorded at a carrying value of $40.9 million, including undiscounted interest payments

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