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FAIR VALUE MEASUREMENTS (Schedule Of Quantitative Inputs And Assumptions For Level 3 Assets And Liabilities) (Details) - USD ($) | 9 Months Ended |
--- | --- | ---
Sep. 30, 2017 | Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Liability | $ 9,300,000 | $ 500,000
Derivative Asset | $ 89,500,000 | 33,100,000
Management Estimate of 62% Fe | 62.00% |
Not Designated as Hedging Instrument [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Liability | $ 9,300,000 | 500,000
Derivative Asset | 89,500,000 | 33,100,000
Fair Value, Inputs, Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Liability | 9,300,000 | 500,000
Derivative Asset | $ 89,500,000 | 31,600,000
Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Managements Estimate Of 62% Fee [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Management Estimate of 62% Fe | 62.00% |
Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Market Approach Valuation Technique [Member] | Provisional Pricing Arrangements [Member] | Managements Estimate Of 62% Fee [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value measurement with unobservable inputs derivative asset range | $ 73 |
Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Market Approach Valuation Technique [Member] | Provisional Pricing Arrangements [Member] | Managements Estimate Of 62% Fee [Member] | Minimum [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value measurement with unobservable inputs derivative asset range | 61 |
Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Market Approach Valuation Technique [Member] | Provisional Pricing Arrangements [Member] | Managements Estimate Of 62% Fee [Member] | Maximum [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value measurement with unobservable inputs derivative asset range | 74 |
Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Market Approach Valuation Technique [Member] | Provisional Pricing Arrangements [Member] | Hot-Rolled Steel Estimate [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value measurement with unobservable inputs derivative asset range | 625 |
Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Market Approach Valuation Technique [Member] | Provisional Pricing Arrangements [Member] | Hot-Rolled Steel Estimate [Member] | Minimum [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value measurement with unobservable inputs derivative asset range | 580 |
Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Market Approach Valuation Technique [Member] | Provisional Pricing Arrangements [Member] | Hot-Rolled Steel Estimate [Member] | Maximum [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value measurement with unobservable inputs derivative asset range | 660 |
Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Market Approach Valuation Technique [Member] | Customer Supply Agreement [Member] | Hot-Rolled Steel Estimate [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value measurement with unobservable inputs derivative asset range | 625 |
Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Market Approach Valuation Technique [Member] | Customer Supply Agreement [Member] | Hot-Rolled Steel Estimate [Member] | Minimum [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value measurement with unobservable inputs derivative asset range | 580 |
Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Market Approach Valuation Technique [Member] | Customer Supply Agreement [Member] | Hot-Rolled Steel Estimate [Member] | Maximum [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value measurement with unobservable inputs derivative asset range | 660 |
Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Market Approach Valuation Technique [Member] | Customer Supply Agreement [Member] | Customer's Hot-Rolled Steel Estimate [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value measurement with unobservable inputs derivative asset range | 565 |
Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Market Approach Valuation Technique [Member] | Customer Supply Agreement [Member] | Customer's Hot-Rolled Steel Estimate [Member] | Minimum [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value measurement with unobservable inputs derivative asset range | 558 |
Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Market Approach Valuation Technique [Member] | Customer Supply Agreement [Member] | Customer's Hot-Rolled Steel Estimate [Member] | Maximum [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value measurement with unobservable inputs derivative asset range | 622 |
Other Current Assets [Member] | Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Market Approach Valuation Technique [Member] | Commodity Contract [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Asset | 0 | 1,500,000
Other Current Liabilities [Member] | Fair Value, Inputs, Level 3 [Member] | Not Designated as Hedging Instrument [Member] | Market Approach Valuation Technique [Member] | Commodity Contract [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Liability | $ 0 | $ 0

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