Basis Of Presentation And Significant Accounting Policies (Narrative) (Details) In Millions, except Per Share data, unless otherwise specified |
3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 6 Months Ended | 9 Months Ended | |||||||||||
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Sep. 30, 2011
USD ($)
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Sep. 30, 2010
USD ($)
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Sep. 30, 2011
USD ($)
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Sep. 30, 2010
USD ($)
|
Dec. 31, 2010
USD ($)
|
Sep. 30, 2011
RenewaFUEL [Member]
USD ($)
|
Sep. 30, 2010
RenewaFUEL [Member]
USD ($)
|
Sep. 30, 2011
RenewaFUEL [Member]
USD ($)
|
Sep. 30, 2010
RenewaFUEL [Member]
USD ($)
|
Sep. 30, 2011
Empire [Member]
USD ($)
|
Jun. 30, 2011
AusQuest [Member]
USD ($)
|
Sep. 30, 2011
WISCO [Member]
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Sep. 30, 2011
Consolidated Thompson [Member]
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May 12, 2011
Consolidated Thompson [Member]
CAD
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Sep. 30, 2011
Earnings Per Share, Basic [Member]
USD ($)
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Sep. 30, 2011
Immaterial Error [Member]
USD ($)
|
Jun. 30, 2011
Immaterial Error [Member]
USD ($)
|
Mar. 31, 2011
Immaterial Error [Member]
USD ($)
|
Jun. 30, 2011
Immaterial Error [Member]
USD ($)
|
Sep. 30, 2011
Immaterial Error [Member]
USD ($)
|
|
| Cost per share acquired | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | 17.25 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Ownership percentage in Consolidated Thompson | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | 100.00% | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Recorded impairment charges | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | $ 17.6 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Interest Percentage | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | 25.00% | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Fair value of AusQuest closing market price | Ìý | Ìý | Ìý | Ìý | 22.0 | Ìý | Ìý | Ìý | Ìý | Ìý | 7.3 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Cost of Rehabilitation, Current | 20 | Ìý | 20 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Investment Owned, Balance, Shares | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | 68.3 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest | 758.8 | 298.1 | 1,609.4 | 637.4 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | 16.1 | 7.7 | 8.4 | 16.1 | 16.1 |
| Earnings Per Share, Basic and Diluted | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | $ 0.47 | $ (0.22) | $ (0.28) | $ (0.49) | Ìý |
| Basic | $ 4.09 | $ 2.20 | $ 10.18 | $ 4.70 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | $ 0.49 |
| Diluted | $ 4.07 | $ 2.18 | $ 10.12 | $ 4.67 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | $ 0.48 |
| Net income (loss) attributable to Cliffs shareholders | 589.5 | 297.4 | 1,420.6 | 635.4 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | 67.9 | (30.4) | (37.5) | (67.9) | 67.9 |
| Retained Earnings (Accumulated Deficit) | 4,266.2 | Ìý | 4,266.2 | Ìý | 2,924.1 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | 67.9 | Ìý | Ìý | Ìý | 67.9 |
| LESS: NET INCOME (LOSS) ATTRIBUTABLE TO NONCONTROLLING INTEREST (net of tax of $0.1, $0.3, and $9.1 in 2010, 2009 and 2008) | 151.8 | Ìý | 170.1 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | 38.1 | 45.9 | 84.0 | 84.0 |
| NONCONTROLLING INTEREST | 1,128.4 | Ìý | 1,128.4 | Ìý | (7.2) | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | 84.0 | Ìý | Ìý | Ìý | 84.0 |
| Reimbursement Revenue And Freight Revenue | 18.4 | 58.8 | 169.4 | 183.1 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | (46.0) | (46.0) | Ìý | (46.0) | (46.0) |
| Sales Revenue, goods, net | 2,124.4 | 1,287.2 | 4,962.4 | 3,074.8 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | 54.1 | 46.0 | 54.1 | 100.1 | 54.1 |
| Related party revenue | 224.9 | Ìý | 313.6 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Related party receivables | 68.8 | Ìý | 68.8 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Total Related Party Revenue | 837.8 | 379.4 | 1,700.0 | 905.4 | Ìý | Ìý | Ìý | Ìý | Ìý | 157.1 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Loss from discontinued operations, net of tax | 17.5 | 0.7 | 18.7 | 2.0 | Ìý | 17.5 | 0.7 | 18.7 | 2.0 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Discontinued Operation, Tax Effect of Discontinued Operation | Ìý | Ìý | Ìý | Ìý | Ìý | 7.3 | 0.4 | 7.9 | 1.0 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Impairment charge | Ìý | Ìý | Ìý | Ìý | Ìý | 16.7 | Ìý | 16.7 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Asset Impairment Charges, Tax Effect | Ìý | Ìý | Ìý | Ìý | Ìý | 7.1 | Ìý | 7.1 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Adjustment to income from continuing operations before income taxes and equity loss from ventures | Ìý | Ìý | 22.0 | 12.3 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Adjustment to net income attributable to shareholders | Ìý | Ìý | 16.1 | 8.9 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Adjustment to basic and diluted earnings per common share | Ìý | Ìý | $ 0.12 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | $ 0.07 | Ìý | Ìý | Ìý | Ìý | Ìý |
| Adjustment to retained earnings | Ìý | Ìý | 16.1 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
| Accumulated other comprehensive income | Ìý | Ìý | Ìý | Ìý | $ 25.3 | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý | Ìý |
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- Definition Asset Impairment Charges, Tax Effect
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- Definition Business Acquisition, Cost Of Acquired Entity, Cash Paid Per Share
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- Definition The consideration for the sale of our interest in one of our equity method investments. The buyer is to assume the cost of rehabilitation.
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- Definition Increase Decrease Earnings Per Share
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- Definition The increase or decrease in accumulated other comprehensive income.
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- Definition Increase Decrease Net Income Loss Available To Common Stockholders
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- Definition Increase Decrease Retained Earnings Accumulated Deficit
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- Definition Increase Decreases Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments
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- Definition Repayment received for expenses incurred on behalf of the client or customer and revenue from transporting freight between locations.
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- Definition For an unclassified balance sheet, amount of receivables arising from transactions with related parties. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The charge against earnings resulting from the aggregate write down of all assets from their carrying value to their fair value. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of voting equity interests acquired in the business combination. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items. Includes the tax effects of the following: income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, and noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This element represents the overall income (loss) from a disposal group that is classified as a component of the entity, net of income tax, reported as a separate component of income before extraordinary items before deduction or consideration of the amount which may be allocable to noncontrolling interests, if any. Includes the following (net of tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Balance held at close of period in number of shares. 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. This item represents investment securities as of the balance sheet date which may include marketable securities, derivative financial instruments, and investments accounted for under the equity method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). 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 portion of net Income or Loss attributable to the noncontrolling interest (if any) deducted in order to derive the portion attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Revenues, net of returns and allowances, realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The cumulative amount of the reporting entity's undistributed earnings or deficit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Revenues arising from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's' management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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