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DEBT AND CREDIT FACILITIES (Debt Instrument Redemption) (Details) | 3 Months Ended
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Mar. 31, 2020
6.75% 2026 Senior Notes [Member] | Debt Instrument, Redemption, Period One, Including Premium [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 100.00%
6.75% 2026 Senior Notes [Member] | Debt Instrument, Redemption, Period One, Upon Equity Issuance [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 106.75%
6.75% 2026 Senior Notes [Member] | Debt Instrument, Redemption, Period Two [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 105.063%
6.75% 2026 Senior Notes [Member] | Debt Instrument, Redemption, Period Three [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 103.375%
6.75% 2026 Senior Notes [Member] | Debt Instrument, Redemption, Period Four [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 101.688%
6.75% 2026 Senior Notes [Member] | Debt Instrument, Redemption, Period Five [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 100.00%
6.375% 2025 Senior Notes [Member] | Debt Instrument, Redemption, Period One, Including Premium [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 100.00%
6.375% 2025 Senior Notes [Member] | Debt Instrument, Redemption, Period One, Upon Equity Issuance [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 106.375%
6.375% 2025 Senior Notes [Member] | Debt Instrument, Redemption, Period Two [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 103.188%
6.375% 2025 Senior Notes [Member] | Debt Instrument, Redemption, Period Three [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 101.594%
6.375% 2025 Senior Notes [Member] | Debt Instrument, Redemption, Period Four [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 100.00%
7.00% 2027 Senior Notes [Member] | Debt Instrument, Redemption, Period One, Including Premium [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 100.00%
7.00% 2027 Senior Notes [Member] | Debt Instrument, Redemption, Period Two [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 103.50%
7.00% 2027 Senior Notes [Member] | Debt Instrument, Redemption, Period Three [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 102.333%
7.00% 2027 Senior Notes [Member] | Debt Instrument, Redemption, Period Four [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 101.167%
7.00% 2027 Senior Notes [Member] | Debt Instrument, Redemption, Period Five [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 100.00%
7.50% 2023 AK Senior Notes [Member] | Debt Instrument, Redemption, Period Two [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 101.875%
7.50% 2023 AK Senior Notes [Member] | Debt Instrument, Redemption, Period Three [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 100.00%
7.50% 2023 AK Senior Notes [Member] | Debt Instrument, Redemption, Period Four [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 103.75%
6.375% 2025 AK Senior Notes [Member] | Debt Instrument, Redemption, Period One, Including Premium [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 100.00%
6.375% 2025 AK Senior Notes [Member] | Debt Instrument, Redemption, Period Two [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 103.188%
6.375% 2025 AK Senior Notes [Member] | Debt Instrument, Redemption, Period Three [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 101.594%
6.375% 2025 AK Senior Notes [Member] | Debt Instrument, Redemption, Period Four [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 100.00%
7.00% 2027 AK Senior Notes [Member] | Debt Instrument, Redemption, Period One, Including Premium [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 100.00%
7.00% 2027 AK Senior Notes [Member] | Debt Instrument, Redemption, Period Two [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 103.50%
7.00% 2027 AK Senior Notes [Member] | Debt Instrument, Redemption, Period Three [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 102.333%
7.00% 2027 AK Senior Notes [Member] | Debt Instrument, Redemption, Period Four [Member] |
Debt Instrument, Redemption [Line Items] |
Debt Instrument, Redemption Price, Percentage | 101.167%

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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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- Definition Percentage price of original principal amount of debt at which debt can be redeemed by the issuer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph e -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 + Details
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