|
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Narrative) (Details) (USD $)
In Millions, unless otherwise specified |
3 Months Ended | ||
|---|---|---|---|
|
Mar. 31, 2013
|
Mar. 31, 2012
|
Dec. 31, 2012
|
|
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net | $ (5.0) | $ 3.7 | Ìý |
| Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net | 2.0 | 3.6 | Ìý |
| Amount of gain/(loss) recognized in income on derivative | (2.0) | Ìý | Ìý |
| Derivative assets | 66.4 | Ìý | 78.6 |
|
Australian Dollar Foreign Exchange Contract Hedge Designation [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net | 3.2 | 3.0 | Ìý |
|
Australian Dollar Foreign Exchange Contract Hedge Designation [Member] | Product Revenues [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net | 1.8 | 3.1 | Ìý |
|
Australian Dollar Foreign Exchange Contract Hedge Designation [Member] | Designated as Hedging Instrument [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Notional amounts of outstanding exchange rate contracts | 378.0 | Ìý | 400.0 |
|
Australian Dollar Foreign Exchange Contract Hedge Designation [Member] | Designated as Hedging Instrument [Member] | Accumulated Other Comprehensive Income (Loss) [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Amount that will be reclassified to product revenues in the next 12 months upon settlement of the related contracts | 8.1 | Ìý | Ìý |
|
Canadian Dollar Foreign Exchange Contracts Hedge Designation [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net | (8.2) | 0.7 | Ìý |
|
Canadian Dollar Foreign Exchange Contracts Hedge Designation [Member] | Cost Of Goods Sold And Operating Expenses [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net | 0.2 | 0.5 | Ìý |
|
Canadian Dollar Foreign Exchange Contracts Hedge Designation [Member] | Designated as Hedging Instrument [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Notional amounts of outstanding exchange rate contracts | 557.3 | Ìý | 630.4 |
|
Canadian Dollar Foreign Exchange Contracts Hedge Designation [Member] | Designated as Hedging Instrument [Member] | Accumulated Other Comprehensive Income (Loss) [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Amount that will be reclassified to product revenues in the next 12 months upon settlement of the related contracts | (5.0) | Ìý | Ìý |
|
Customer Supply Agreement [Member] | Not Designated as Hedging Instrument [Member] | Product Revenues [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Amount of gain/(loss) recognized in income on derivative | 24.1 | 39.2 | Ìý |
|
Customer Supply Agreement [Member] | Not Designated as Hedging Instrument [Member] | Derivative Assets [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Derivative assets | 49.4 | Ìý | 58.9 |
|
Provisional Pricing Arrangements [Member] | Not Designated as Hedging Instrument [Member] | U.S. Iron Ore and Asia Pacific Iron Ore [Member] | Product Revenues [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Amount of gain/(loss) recognized in income on derivative | (2.9) | Ìý | Ìý |
|
Provisional Pricing Arrangements [Member] | Not Designated as Hedging Instrument [Member] | U.S. Iron Ore and Asia Pacific Iron Ore [Member] | Derivative Assets [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Derivative assets | 3.9 | Ìý | Ìý |
|
Provisional Pricing Arrangements [Member] | Not Designated as Hedging Instrument [Member] | U.S. Iron Ore and Asia Pacific Iron Ore [Member] | Other Current Liabilities [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Derivative liabilities | 6.8 | Ìý | Ìý |
|
Provisional Pricing Arrangements [Member] | Not Designated as Hedging Instrument [Member] | U.S. Iron Ore, Eastern Canadian Iron Ore And Asia Pacific Iron Ore [Member] | Product Revenues [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Amount of gain/(loss) recognized in income on derivative | Ìý | 3.0 | Ìý |
|
Provisional Pricing Arrangements [Member] | Not Designated as Hedging Instrument [Member] | U.S. Iron Ore and Eastern Canadian Iron Ore [Member] | Derivative Assets [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Derivative assets | Ìý | Ìý | 3.5 |
|
Provisional Pricing Arrangements [Member] | Not Designated as Hedging Instrument [Member] | U.S. Iron Ore and Eastern Canadian Iron Ore [Member] | Other Current Liabilities [Member]
|
Ìý | Ìý | Ìý |
| Derivative [Line Items] | Ìý | Ìý | Ìý |
| Derivative liabilities | Ìý | Ìý | $ 11.3 |