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DEBT AND CREDIT FACILITIES (Schedule Of Long-Term Debt) (Details) - USD ($) | Jun. 30, 2018 | Mar. 31, 2018 | Jan. 01, 2018 | Dec. 31, 2017
--- | --- | --- | --- | ---
Debt Instrument [Line Items] |  |  |  |
LONG-TERM DEBT | $ 2,297,000,000 |  | $ 2,304,200,000 | $ 2,304,200,000
$400 Million 4.875% 2024 Senior Notes [Domain] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 5.00% |  |  | 5.00%
Debt Instrument, Par Value | $ 400,000,000 |  |  | $ 400,000,000
Unamortized Debt Issuance Expense | (6,300,000) |  |  | (7,100,000)
Debt Instrument, Unamortized Discount | (2,400,000) |  |  | (2,600,000)
Long-term Debt | $ 391,300,000 |  |  | $ 390,300,000
$400 Million 5.90% 2020 Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 5.98% |  |  | 5.98%
Debt Instrument, Par Value | $ 88,400,000 |  |  | $ 88,900,000
Unamortized Debt Issuance Expense | (200,000) |  |  | (200,000)
Debt Instrument, Unamortized Discount | (100,000) |  |  | (100,000)
Long-term Debt | $ 88,100,000 |  |  | $ 88,600,000
$500 million 4.80% 2020 Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 4.83% |  |  | 4.83%
Debt Instrument, Par Value | $ 122,300,000 |  |  | $ 122,400,000
Unamortized Debt Issuance Expense | (200,000) |  |  | (300,000)
Debt Instrument, Unamortized Discount | (100,000) |  |  | (100,000)
Long-term Debt | $ 122,000,000 |  |  | $ 122,000,000
$700 Million 4.875% 2021 Senior Note [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 4.89% |  |  | 4.89%
Debt Instrument, Par Value | $ 125,200,000 |  |  | $ 138,400,000
Unamortized Debt Issuance Expense | (300,000) |  |  | (300,000)
Debt Instrument, Unamortized Discount | 0 |  |  | (100,000)
Long-term Debt | $ 124,900,000 |  |  | $ 138,000,000
$316 Million 1.5% 2025 Senior Notes [Domain] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 6.26% |  |  | 6.26%
Debt Instrument, Par Value | $ 316,300,000 |  |  | $ 316,300,000
Unamortized Debt Issuance Expense | (6,000,000) |  |  | (6,600,000)
Debt Instrument, Unamortized Discount | (80,600,000) |  |  | (85,600,000)
Long-term Debt | $ 229,700,000 |  |  | $ 224,100,000
$1,075 Million 5.75% 2025 Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 6.01% |  |  | 6.01%
Debt Instrument, Par Value | $ 1,073,300,000 |  |  | $ 1,075,000,000
Unamortized Debt Issuance Expense | (10,600,000) |  |  | (11,300,000)
Debt Instrument, Unamortized Discount | (15,600,000) |  |  | (16,500,000)
Long-term Debt | $ 1,047,100,000 |  |  | $ 1,047,200,000
$800 Million 6.25% 2040 Senior Notes [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 6.34% |  |  | 6.34%
Debt Instrument, Par Value | $ 298,400,000 |  |  | $ 298,400,000
Unamortized Debt Issuance Expense | (2,300,000) |  |  | (2,400,000)
Debt Instrument, Unamortized Discount | (3,400,000) |  |  | (3,400,000)
Long-term Debt | 292,700,000 |  |  | 292,600,000
Revolving Credit Facility [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Par Value | 450,000,000 | $ 450,000,000 |  | 550,000,000
Credit facility, amount outstanding | 0 |  |  | 0
Interest Rate Swap [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Fair Value Adjustment to Interest Rate Hedge | $ 1,200,000 |  |  | $ 1,400,000

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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 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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