Shareholders' Equity And Comprehensive Income (Components Of Comprehensive Income) (Details) (USD $) In Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2011 |
Sep. 30, 2010 |
Sep. 30, 2011 |
Sep. 30, 2010 |
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| Shareholders' Equity And Comprehensive Income [Abstract] | ||||
| Net income attributable to Cliffs shareholders | $ 589.5 | $ 297.4 | $ 1,420.6 | $ 635.4 |
| Unrealized net gain (loss) on marketable securities - net of tax | (11.6) | 14.5 | (30.8) | 0.3 |
| Foreign currency translation | (132.2) | 145.8 | (74.8) | 101.5 |
| Amortization of net periodic benefit cost - net of tax | 5.3 | (0.5) | 13.9 | 42.5 |
| Reclassification of net gains on derivative financial instruments into net income | (1.5) | (3.2) | (3.2) | |
| Unrealized loss on derivative financial instruments | (15.2) | (10.3) | ||
| Total other comprehensive income (loss) | (155.2) | 159.8 | (105.2) | 141.1 |
| Total comprehensive income | $ 434.3 | $ 457.2 | $ 1,315.4 | $ 776.5 |
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- Definition Comprehensive Income [Abstract]
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- Definition The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The adjustment out of other comprehensive income for prior service costs recognized as a component of net period benefit cost during the period, after tax. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency of the reporting entity, net of tax. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This element represents Other Comprehensive Income or Loss, Before Tax, for the period. The pretax revenues, expenses, gains, and losses that under generally accepted accounting principles are included in comprehensive income, but excluded from net income. Includes the entity's proportionate share of an investee's equity adjustments for other comprehensive income. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Net of tax effect of the reclassification adjustment for accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was realized in net income during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Change in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges, net of tax effect. The after tax effect change includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Appreciation or loss in value (before reclassification adjustment) of the total of unsold securities during the period being reported on, net of tax. Reclassification adjustments include: (1) the unrealized holding gain (loss), net of tax, at the date of the transfer for a debt security from the held-to-maturity category transferred into the available-for-sale category. Also includes the unrealized gain (loss) at the date of transfer for a debt security from the available-for-sale category transferred into the held-to-maturity category; (2) the unrealized gains (losses) realized upon the sale of securities, after tax; and (3) the unrealized gains (losses) realized upon the write-down of securities, after tax. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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