Fair Value Of Financial Instruments (Narrative) (Details) (USD $) In Millions, unless otherwise specified |
1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended | 12 Months Ended | |||||||
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Sep. 30, 2009 |
Jun. 30, 2011 |
Sep. 30, 2010 |
Sep. 30, 2011 |
Sep. 30, 2010 |
Dec. 31, 2010 |
Dec. 31, 2010
Empire [Member]
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Sep. 30, 2011
Empire [Member]
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Dec. 31, 2002
Empire [Member]
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Dec. 31, 2010
U.S. Iron Ore [Member]
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Dec. 31, 2013
U.S. Iron Ore [Member]
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Sep. 30, 2011
U.S. Iron Ore [Member]
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| Financial assets or liabilities measured at fair value on a non-recurring basis | $ 0 | |||||||||||
| Fair value transfers amount between Level 1 and Level 2 | 0 | |||||||||||
| Interest rate on long term receivable | 9 | |||||||||||
| Percent ownership interest | 79.00% | 46.70% | ||||||||||
| Transfers out of Level 3 | 161.8 | 20.0 | 161.8 | |||||||||
| Long-term receivables | 32.8 | 28.1 | 120.0 | 22.3 | 22.3 | 22.3 | ||||||
| Fair value of the receivable | 38.9 | 32.7 | 19.5 | 20.5 | ||||||||
| Estimated credit-adjusted risk-free interest rate | 3.10% | 4.70% | ||||||||||
| Basis points | 350 | |||||||||||
| Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, transfers out of Level 3 | $ 20.0 | $ (161.8) | ||||||||||
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- Definition Basis Points
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- Definition Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level Three
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- Definition Financial assets or liabilities measured at fair value on a non-recurring basis
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- Definition The percentage of ownership of common stock or equity participation in the investee.
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- Definition Risk Free Discount Rate
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- Definition The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.
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- Definition The amount of the transfers of assets or liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Transfers out of assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate of amounts due from customers or clients more than one year from the balance sheet date, for goods or services that have been delivered or sold in the normal course of business and an amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money at a future date more than one year from the balance sheet date, reduced to their estimated net realizable fair value by an allowance established by the Company of the amount it deems uncertain of collection and net of any write-downs taken for collection uncertainty on the part of the holder, respectively. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. Includes disclosure of claims held for amounts due a company. Examples include trade accounts receivables, notes receivables, loans receivables. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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