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DERIVATIVE INSTRUMENTS (Schedule Of Derivative Instruments In Statement Of Financial Position, Fair Value) (Details) - USD ($) $ in Millions | Mar. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Commodity Contract [Member] | Derivative Asset [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset | $ 1.6 |
Commodity Contract [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | 26.5 | $ 3.2
Commodity Contract [Member] | Other Noncurrent Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | 3.4 |
Foreign Exchange Contract [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | 1.6 |
Foreign Exchange Contract [Member] | Other Noncurrent Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | 0.9 |
Customer Supply Agreement [Member] | Derivative Asset [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset | 19.0 | 44.5
Provisional Pricing Arrangements [Member] | Derivative Asset [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset | 0.6 | 1.3
Provisional Pricing Arrangements [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability |  | 1.1
Fair Value, Inputs, Level 2 [Member] | Commodity Contract [Member] | Derivative Asset [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset | 1.6 |
Fair Value, Inputs, Level 2 [Member] | Commodity Contract [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | 26.5 | 3.2
Fair Value, Inputs, Level 2 [Member] | Commodity Contract [Member] | Other Noncurrent Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | 3.4 |
Fair Value, Inputs, Level 2 [Member] | Foreign Exchange Contract [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | 1.6 |
Fair Value, Inputs, Level 2 [Member] | Foreign Exchange Contract [Member] | Other Noncurrent Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | 0.9 |
Fair Value, Inputs, Level 2 [Member] | Customer Supply Agreement [Member] | Derivative Asset [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset |  | 0.0
Fair Value, Inputs, Level 2 [Member] | Provisional Pricing Arrangements [Member] | Derivative Asset [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset |  | 0.0
Fair Value, Inputs, Level 2 [Member] | Provisional Pricing Arrangements [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability |  | 0.0
Fair Value, Inputs, Level 3 [Member] | Commodity Contract [Member] | Derivative Asset [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset | 0.0 |
Fair Value, Inputs, Level 3 [Member] | Commodity Contract [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | 0.0 | 0.0
Fair Value, Inputs, Level 3 [Member] | Customer Supply Agreement [Member] | Derivative Asset [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset | 19.0 | 44.5
Fair Value, Inputs, Level 3 [Member] | Provisional Pricing Arrangements [Member] | Derivative Asset [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset | 0.6 | 1.3
Fair Value, Inputs, Level 3 [Member] | Provisional Pricing Arrangements [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability |  | 1.1
Valuation, Market Approach [Member] | Fair Value, Inputs, Level 2 [Member] | Designated as Hedging Instrument [Member] | Commodity Contract [Member] | Derivative Asset [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset | 0.3 | 0.0
Valuation, Market Approach [Member] | Fair Value, Inputs, Level 2 [Member] | Designated as Hedging Instrument [Member] | Commodity Contract [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | (25.9) | (3.2)
Valuation, Market Approach [Member] | Fair Value, Inputs, Level 2 [Member] | Designated as Hedging Instrument [Member] | Commodity Contract [Member] | Other Noncurrent Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | (2.8) | 0.0
Valuation, Market Approach [Member] | Fair Value, Inputs, Level 2 [Member] | Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | (1.6) | 0.0
Valuation, Market Approach [Member] | Fair Value, Inputs, Level 2 [Member] | Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member] | Other Noncurrent Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | (0.9) | 0.0
Valuation, Market Approach [Member] | Fair Value, Inputs, Level 2 [Member] | Not Designated as Hedging Instrument [Member] | Commodity Contract [Member] | Derivative Asset [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset | 1.3 | 0.0
Valuation, Market Approach [Member] | Fair Value, Inputs, Level 2 [Member] | Not Designated as Hedging Instrument [Member] | Commodity Contract [Member] | Other Current Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | (0.6) | 0.0
Valuation, Market Approach [Member] | Fair Value, Inputs, Level 2 [Member] | Not Designated as Hedging Instrument [Member] | Commodity Contract [Member] | Other Noncurrent Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative liability | (0.6) | 0.0
Valuation, Market Approach [Member] | Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Customer Supply Agreement [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset | 19.0 | 44.5
Valuation, Market Approach [Member] | Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Provisional Pricing Arrangements [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset | 0.6 | 1.3
Derivative liability | $ 0.0 | $ (1.1)

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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 + Details
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