ASSET RETIREMENT OBLIGATIONS - Summary Of Asset Retirement Obligations (Details) - USD ($) $ in Millions |
9 Months Ended | |||
|---|---|---|---|---|
Sep. 30, 2020 |
Sep. 30, 2019 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Environmental Exit Cost [Line Items] | Ìý | Ìý | Ìý | Ìý |
| Asset Retirement Obligation | $ 186.4 | $ 179.5 | $ 165.3 | $ 172.4 |
| Asset Retirement Obligation, Current | 4.4 | Ìý | 2.1 | Ìý |
| Long-term asset retirement obligations | 182.0 | Ìý | 163.2 | Ìý |
| Increase from AK Steel acquisition | 16.7 | $ 0.0 | Ìý | Ìý |
| Operating Segments [Member] | Ìý | Ìý | Ìý | Ìý |
| Environmental Exit Cost [Line Items] | Ìý | Ìý | Ìý | Ìý |
| Asset Retirement Obligation | $ 33.7 | Ìý | $ 22.0 | Ìý |
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- Definition Asset Retirement Obligation, Liabilities Assumed, Acquisition No definition available.
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- Definition The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. No definition available.
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- Details
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