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DEBT AND CREDIT FACILITIES (Narrative) (Details) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2017 USD ($) | Jun. 30, 2016 USD ($) | Jun. 30, 2017 USD ($) | Jun. 30, 2016 USD ($) | Dec. 31, 2016 USD ($)
Line of Credit Facility [Line Items] |  |  |  |  |
Payments of Debt Issuance Costs |  |  | $ 8,500,000 | $ 5,200,000 |
Gain (loss) on extinguishment/restructuring of debt | $ (4,900,000) | $ 3,600,000 | (76,800,000) | $ 182,400,000 |
Debt redemption premiums paid | 2,900,000 |  | 47,600,000 |  |
$500 Million 5.75% 2025 Senior Notes [Member] |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |
Debt Instrument, Par Value | $ 500,000,000 |  | $ 500,000,000 |  |
Debt Instrument, Interest Rate, Effective Percentage | 5.75% |  | 5.75% |  |
Note Redemption Price, Percent of Principal Amount to be Redeemed | 100.00% |  | 100.00% |  |
Amount in aggregate that can be redeemed on or prior to March 1, 2020 |  |  | 0.3500 |  |
Repurchase price if triggering event occurs |  |  | 1.01 |  |
Redemption Price of 35 percent or less of Outstanding |  |  | 1.0575 |  |
In the Event of Default Amount that will Accelerate |  |  | 0.25 |  |
Unamortized Debt Issuance Expense | $ 8,100,000 |  | $ 8,100,000 |  |
Revolving Credit Facility [Member] |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |
Credit facility, amount outstanding | 0 |  | 0 |  | $ 0
Line of Credit Facility, Maximum Borrowing Capacity | 296,600,000 |  | 296,600,000 |  | 333,000,000
Debt Instrument, Par Value | 550,000,000 |  | 550,000,000 |  | 550,000,000
Letters of credit outstanding | 82,500,000 |  | 82,500,000 |  | 106,000,000
Credit facility remaining capacity | $ 214,100,000 |  | $ 214,100,000 |  | $ 227,000,000

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- Definition Amount in aggregate that can be redeemed on or prior to March 1, 2020 + References No definition available. + Details
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- Definition Debt redemption premiums paid + References No definition available. + Details
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- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + 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(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 + Details
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- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629 + Details
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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 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 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 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 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + 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 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 The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585 + Details
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