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DEBT AND CREDIT FACILITIES DEBT AND CREDIT FACILITIES (Schedule of Extinguishment of Debt) (Details) - USD ($) $ in Millions | Jun. 30, 2018 | Dec. 31, 2017
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$400 Million 5.90% 2020 Senior Notes [Member] |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Par Value | $ 88.4 | $ 88.9
$1,075 Million 5.75% 2025 Senior Notes [Member] |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Par Value | 1,073.3 | 1,075.0
$500 million 4.80% 2020 Senior Notes [Member] |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Par Value | 122.3 | 122.4
$700 Million 4.875% 2021 Senior Note [Member] |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Par Value | 125.2 | $ 138.4
Debt Repurchase [Member] |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Par Value | 15.5 |
Debt Repurchase [Member] | $400 Million 5.90% 2020 Senior Notes [Member] |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Par Value | 0.5 |
Debt Repurchase [Member] | $1,075 Million 5.75% 2025 Senior Notes [Member] |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Par Value | 1.7 |
Debt Repurchase [Member] | $500 million 4.80% 2020 Senior Notes [Member] |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Par Value | 0.1 |
Debt Repurchase [Member] | $700 Million 4.875% 2021 Senior Note [Member] |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Par Value | $ 13.2 |

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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- Details
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- Details
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- Details
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Balance Type: |
Period Type: |