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DEBT AND CREDIT FACILITIES (Schedule Of Long-Term Debt) (Details) - USD ($) $ in Millions | 9 Months Ended |  |  |
--- | --- | --- | --- | ---
Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt Instrument, Face Amount Received in Debt Exchange of $500M 3.95% Notes |  |  |  |  | $ 10.0 |  |
Debt Instrument, Face Amount Received in Debt Exchange of $500M 4.80% Notes |  | $ 4.5 |  | $ 12.6 |  |  |
Debt instrument, Face Amount Received in Debt Exchange of $700M 4.875% Notes |  | 10.5 |  |  |  |  |
Total Face Amount |  | 2,833.1 |  |  |  | $ 3,448.2 |
Letters of credit outstanding |  | 108.8 |  |  |  | 186.3 |
Long-term Debt |  | 2,195.9 |  |  |  | 2,699.4 |
Debt, Long-term and Short-term, Combined Amount |  | 2,213.4 |  |  |  |  |
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 |  | 325.7 | [1] |  |  | 412.5 |
Unamortized Debt Issuance Expense |  | (1.2) | [1] |  |  | (1.7) |
Long-term Debt |  | 324.3 | [1] |  |  | 410.6 |
Debt Instrument, Unamortized Discount |  | $ (0.2) | [1] |  |  | $ (0.2) |
Imputed interest rate |  | 4.89% | [1] |  |  | 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 |  | 244.8 | [2] |  |  | $ 306.7 |
Unamortized Debt Issuance Expense |  | (0.7) | [2] |  |  | (1.1) |
Long-term Debt |  | 243.9 | [2] |  |  | 305.2 |
Debt Instrument, Unamortized Discount |  | $ (0.2) | [2] |  |  | $ (0.4) |
Imputed interest rate |  | 4.83% | [2] |  |  | 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 | [3] |  |  | $ 492.8 |
Unamortized Debt Issuance Expense |  | (2.5) | [3] |  |  | (4.3) |
Long-term Debt |  | 292.5 | [3] |  |  | 482.7 |
Debt Instrument, Unamortized Discount |  | $ (3.4) | [3] |  |  | $ (5.8) |
Imputed interest rate |  | 6.34% | [3] |  |  | 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 | [4] |  |  | $ 290.8 |
Unamortized Debt Issuance Expense |  | (0.7) | [4] |  |  | (1.1) |
Long-term Debt |  | 224.4 | [4] |  |  | 288.9 |
Debt Instrument, Unamortized Discount |  | $ (0.5) | [4] |  |  | $ (0.8) |
Imputed interest rate |  | 5.98% | [4] |  |  | 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 |  | 0.0 | [5] |  |  | $ 311.2 |
Unamortized Debt Issuance Expense |  | 0.0 | [5] |  |  | (0.9) |
Long-term Debt |  | 0.0 | [5] |  |  | 309.1 |
Debt Instrument, Unamortized Discount |  | $ 0.0 | [5] |  |  | $ (1.2) |
Imputed interest rate |  | 6.15% | [5] |  |  | 6.30% |
$540 Million 8.25% 2020 Lien Notes [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Stated interest rate |  | 8.25% |  |  |  |  |
Total Face Amount |  | $ 540.0 |  |  |  | $ 540.0 |
Unamortized Debt Issuance Expense |  | (8.6) |  |  |  | (10.5) |
Long-term Debt |  | 504.0 |  |  |  | 497.4 |
Debt Instrument, Unamortized Discount |  | $ (27.4) |  |  |  | $ (32.1) |
Imputed interest rate |  | 9.97% |  |  |  | 9.97% |
$218.5 Million 8.00% 2020 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 |  | $ 77.5 |  |  |  |  |
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 |  | 15.5 |  |  |  |  |
Debt Instrument, Carrying Amount Received in Debt Exchange of $400M 5.90% Notes |  | 35.4 |  |  |  |  |
Debt Instrument, Carrying Value Received in Debt Exchange of $800M 6.25% Notes |  | 103.0 |  |  |  |  |
Debt Instrument, Carrying Value Received in Debt Exchange of $500M 4.80% Notes |  | 24.4 |  |  |  |  |
Debt instrument, Carrying Value Received in Debt Exchange of $700M 4.875% Notes |  | 41.5 |  |  |  |  |
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 | [6] | 218.5 |  |  |  |  |
Debt Instrument, Par Value |  | 218.5 |  |  |  |  |
Unamortized Debt Issuance Expense | [6] | 0.0 |  |  |  |  |
Undiscounted interest | [6] | 70.0 |  |  |  |  |
Long-term Debt | [6] | $ 288.5 |  |  |  |  |
$544 Million 7.75% 2020 Lien Notes[Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Stated interest rate |  | 7.75% |  |  |  |  |
Debt Instrument, Face Amount Exchanged |  | $ 114.1 |  |  |  |  |
Total Face Amount |  | 430.1 | [7] |  |  | $ 544.2 |
Unamortized Debt Issuance Expense |  | (6.2) | [7] |  |  | (9.5) |
Long-term Debt |  | 333.8 | [7] |  |  | 403.2 |
Debt Instrument, Unamortized Discount |  | $ (90.1) | [7] |  |  | $ (131.5) |
Imputed interest rate |  | 15.55% | [7] |  |  | 15.55% |
Revolving Credit Facility [Member] |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt Instrument, Par Value |  | $ 550.0 | [8] |  |  | $ 550.0 | [9]
Credit facility, amount outstanding | [8] | 0.0 |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  | 355.7 |  |  |  | 366.0 |
Letters of credit outstanding |  | 108.8 |  |  |  | 186.3 |
Credit facility remaining capacity |  | 246.9 |  |  |  | 179.2 |
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 |  | $ 2.0 |  |  |  | $ 2.3 |
[1] | 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 were recorded at a carrying value of $41.5 million, including undiscounted interest payments
[2] | 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 were recorded at a carrying value of $24.4 million, including undiscounted interest payments as of the transaction date. Additionally, during the second and third quarters of 2016 we entered into a debt for equity exchange; see NOTE 15 - CAPITAL STOCK for further discussion of this transaction.
[3] | 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 were recorded at a carrying value of $103.0 million, including undiscounted interest payments as of the transaction date.
[4] | 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 were recorded at a carrying value of $35.4 million, including undiscounted interest payments as of the transaction date.
[5] | 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 were recorded at a carrying value of $15.5 million, including undiscounted interest payments as of the transaction date. 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.
[6] | 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.
[7] | 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 were recorded at a carrying value of $77.5 million, including undiscounted interest payments as of the transaction date.
[8] | As of September 30, 2016, no loans were drawn under the ABL Facility and we had total availability of $355.7 million as a result of borrowing base limitations. As of September 30, 2016, the principal amount of letter of credit obligations totaled $108.8 million, thereby further reducing available borrowing capacity on our ABL Facility to $246.9 million.
[9] | 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.

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- Definition The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset. + 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 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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