| **Long-term Debt - Table 2 (Details) (USD $)In Millions, unless otherwise specified** | Sep. 30, 2012 | Dec. 31, 2011 |
|---------------------------------------------------------------------------------------|---------------|---------------|
| **Long-term Debt by Maturity**                                                        |          |          |
| Total debt and capital lease obligations                                              | $ 1,321.9     | $ 1,254.7     |
| Face Amount [Member]                                                                  |          |          |
| **Long-term Debt by Maturity**                                                        |          |          |
| October 1 through December 31, 2012                                                   | 67.5          |          |
| 2013                                                                                  | 14.2          |          |
| 2014                                                                                  | 10.5          |          |
| 2015                                                                                  | 8.0           |          |
| 2016                                                                                  | 8.0           |          |
| 2017                                                                                  | 7.1           |          |
| Thereafter                                                                            | 1,207.1       |          |
| Total debt and capital lease obligations                                              | 1,322.4       |          |
| Net Amount [Member]                                                                   |          |          |
| **Long-term Debt by Maturity**                                                        |          |          |
| October 1 through December 31, 2012                                                   | 67.8          |          |
| 2013                                                                                  | 14.2          |          |
| 2014                                                                                  | 10.5          |          |
| 2015                                                                                  | 8.0           |          |
| 2016                                                                                  | 8.0           |          |
| 2017                                                                                  | 7.1           |          |
| Thereafter                                                                            | 1,206.3       |          |
| Total debt and capital lease obligations                                              | $ 1,321.9     |          |

| X                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the remainder of the year.
+ References
No definition available.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year.
+ References
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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year.
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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.
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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year.
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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year.
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