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FAIR VALUE OF FINANCIAL INSTRUMENTS (Carrying Value And Fair Value Of Financial Instruments Disclosure) (Details) - USD ($) | Dec. 31, 2015 | Mar. 31, 2015 | Dec. 31, 2014
--- | --- | --- | ---
Long-term debt: |  |  |
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] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Debt Instrument, Face Amount | 700,000,000 |  | 700,000,000
Senior Notes - $1.3 Billion [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Debt Instrument, Face Amount | 1,300,000,000.0 |  | 1,300,000,000.0
Senior Notes - $400 Million [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Debt Instrument, Face Amount | 400,000,000 |  | 400,000,000
$500 Million 3.95% 2018 Senior Notes [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Debt Instrument, Face Amount | 500,000,000 |  | 500,000,000.0
Interest Rate Swap [Member] |  |  |
Long-term debt: |  |  |
Fair Value Adjustment to Interest Rate Hedge | 2,300,000 |  | 2,800,000
Five hundred Forty-four Million Seven Point Seven Five Twenty Twenty Second Lien Notes [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Debt Instrument, Face Amount | 544,200,000 |  | 0
Long-term debt: |  |  |
Debt Instrument, Fair Value Disclosure |  | $ 397,200,000 |
Five hundred forty million Eight point two five Twenty twenty First Lien Notes [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Debt Instrument, Face Amount | 540,000,000 |  | 0
Fair Value, Inputs, Level 2 [Member] |  |  |
Long-term debt: |  |  |
Long-term Debt, Fair Value | 898,200,000 |  | 1,614,200,000
Fair Value, Inputs, Level 2 [Member] | Seven Hundred Million Four Point Eight Seven Five Two Thousand Twenty-one Senior Note [Member] |  |  |
Long-term debt: |  |  |
Debt Instrument, Fair Value Disclosure | 69,400,000 |  | 367,300,000
Fair Value, Inputs, Level 2 [Member] | Senior Notes - $1.3 Billion [Member] |  |  |
Long-term debt: |  |  |
Debt Instrument, Fair Value Disclosure | 137,400,000 |  | 704,000,000
Fair Value, Inputs, Level 2 [Member] | Senior Notes - $400 Million [Member] |  |  |
Long-term debt: |  |  |
Debt Instrument, Fair Value Disclosure | 52,800,000 |  | 228,100,000
Fair Value, Inputs, Level 2 [Member] | $500 Million 3.95% 2018 Senior Notes [Member] |  |  |
Long-term debt: |  |  |
Debt Instrument, Fair Value Disclosure | 87,100,000 |  | 312,000,000
Fair Value, Inputs, Level 2 [Member] | Revolving Credit Facility [Member] |  |  |
Long-term debt: |  |  |
Revolving loan, fair value | 0 |  | 0
Fair Value, Inputs, Level 2 [Member] | Interest Rate Swap [Member] |  |  |
Long-term debt: |  |  |
Fair Value Adjustment to Interest Rate Hedge | 2,300,000 |  | 2,800,000
Fair Value, Inputs, Level 2 [Member] | Five hundred Forty-four Million Seven Point Seven Five Twenty Twenty Second Lien Notes [Member] |  |  |
Long-term debt: |  |  |
Debt Instrument, Fair Value Disclosure | 134,700,000 | $ 397,200,000 | 0
Fair Value, Inputs, Level 2 [Member] | Five hundred forty million Eight point two five Twenty twenty First Lien Notes [Member] |  |  |
Long-term debt: |  |  |
Debt Instrument, Fair Value Disclosure | 414,500,000 |  | 0
Reported Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Long-term debt: |  |  |
LONG-TERM DEBT | 2,699,400,000 |  | 2,826,500,000
Reported Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] | Seven Hundred Million Four Point Eight Seven Five Two Thousand Twenty-one Senior Note [Member] |  |  |
Long-term debt: |  |  |
Senior notes, carrying value | 410,600,000 |  | 686,000,000
Reported Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] | Senior Notes - $1.3 Billion [Member] |  |  |
Long-term debt: |  |  |
Senior notes, carrying value | 787,900,000 |  | 1,270,500,000
Reported Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] | Senior Notes - $400 Million [Member] |  |  |
Long-term debt: |  |  |
Senior notes, carrying value | 288,900,000 |  | 391,900,000
Reported Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] | $500 Million 3.95% 2018 Senior Notes [Member] |  |  |
Long-term debt: |  |  |
Senior notes, carrying value | 309,100,000 |  | 475,300,000
Reported Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] | Revolving Credit Facility [Member] |  |  |
Long-term debt: |  |  |
Senior notes, carrying value | 0 |  | 0
Reported Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] | Interest Rate Swap [Member] |  |  |
Long-term debt: |  |  |
Fair Value Adjustment to Interest Rate Hedge | 2,300,000 |  | 2,800,000
Reported Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] | Five hundred Forty-four Million Seven Point Seven Five Twenty Twenty Second Lien Notes [Member] |  |  |
Long-term debt: |  |  |
Senior notes, carrying value | 403,200,000 |  | 0
Reported Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] | Five hundred forty million Eight point two five Twenty twenty First Lien Notes [Member] |  |  |
Long-term debt: |  |  |
Senior notes, carrying value | $ 497,400,000 |  | $ 0

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