|
Fair Value Of Financial Instruments (Carrying Value And Fair Value Of Financial Instruments Disclosure) (Details) (USD $)
In Millions, unless otherwise specified |
Dec. 31, 2011
|
Dec. 31, 2010
|
|---|---|---|
| Long-term debt: | ||
| Customer Borrowings | $ 972.0 | |
| Total long-term debt | 3,608.7 | 1,713.1 |
|
Carrying Value [Member]
|
||
| Long-term receivables: | ||
| Receivables | 58.8 | 63.2 |
| Long-term debt: | ||
| Customer Borrowings | 5.1 | 4.0 |
| Total long-term debt | 3,613.8 | 1,717.1 |
|
Carrying Value [Member] | Customer Supplemental Payments [Member]
|
||
| Long-term receivables: | ||
| Receivables | 22.3 | 22.3 |
|
Carrying Value [Member] | ArcelorMittal USA Receivable [Member]
|
||
| Long-term receivables: | ||
| Receivables | 26.5 | 32.8 |
|
Carrying Value [Member] | Other Credit Receivable [Member]
|
||
| Long-term receivables: | ||
| Receivables | 10.0 | 8.1 |
|
Fair Value [Member]
|
||
| Long-term receivables: | ||
| Receivables | 61.5 | 66.5 |
| Long-term debt: | ||
| Customer Borrowings | 5.1 | 4.0 |
| Long Term Debt Noncurrent Fair Value | 3,825.6 | 1,754.9 |
|
Fair Value [Member] | Customer Supplemental Payments [Member]
|
||
| Long-term receivables: | ||
| Receivables | 20.8 | 19.5 |
|
Fair Value [Member] | ArcelorMittal USA Receivable [Member]
|
||
| Long-term receivables: | ||
| Receivables | 30.7 | 38.9 |
|
Fair Value [Member] | Other Credit Receivable [Member]
|
||
| Long-term receivables: | ||
| Receivables | 10.0 | 8.1 |
|
Term Notes One Point Two Five Billion [Member]
|
||
| Long-term debt: | ||
| Term loan | 1,250.0 | |
|
Term Notes One Point Two Five Billion [Member] | Carrying Value [Member]
|
||
| Long-term debt: | ||
| Term loan | 897.2 | |
|
Term Notes One Point Two Five Billion [Member] | Fair Value [Member]
|
||
| Long-term debt: | ||
| Term loan | 897.2 | |
|
Senior Notes Seven Hundred Million [Member]
|
||
| Long-term debt: | ||
| Senior notes | 700.0 | |
|
Senior Notes Seven Hundred Million [Member] | Carrying Value [Member]
|
||
| Long-term debt: | ||
| Senior notes | 699.3 | |
|
Senior Notes Seven Hundred Million [Member] | Fair Value [Member]
|
||
| Long-term debt: | ||
| Senior notes | 726.4 | |
|
Senior Notes One Point Three Billion [Member]
|
||
| Long-term debt: | ||
| Senior notes | 1,300.0 | |
|
Senior Notes One Point Three Billion [Member] | Carrying Value [Member]
|
||
| Long-term debt: | ||
| Senior notes | 1,289.2 | 990.3 |
|
Senior Notes One Point Three Billion [Member] | Fair Value [Member]
|
||
| Long-term debt: | ||
| Senior notes | 1,399.4 | 972.5 |
|
Senior Notes Four Hundred Million [Member]
|
||
| Long-term debt: | ||
| Senior notes | 400.0 | |
|
Senior Notes Four Hundred Million [Member] | Carrying Value [Member]
|
||
| Long-term debt: | ||
| Senior notes | 398.0 | 397.8 |
|
Senior Notes Four Hundred Million [Member] | Fair Value [Member]
|
||
| Long-term debt: | ||
| Senior notes | 448.8 | 422.8 |
|
Senior Notes Three Hundred Twenty Five Million [Member]
|
||
| Long-term debt: | ||
| Senior notes | 325.0 | |
|
Senior Notes Three Hundred Twenty Five Million [Member] | Carrying Value [Member]
|
||
| Long-term debt: | ||
| Senior notes | 325.0 | 325.0 |
|
Senior Notes Three Hundred Twenty Five Million [Member] | Fair Value [Member]
|
||
| Long-term debt: | ||
| Senior notes | $ 348.7 | $ 355.6 |