Fair Value of Other Instruments (Details) (USD $) In Millions	Dec. 31, 2010	Dec. 31, 2009
Other Financial Instruments [Abstract]
Notes Receivable - Carrying Value	$ 7.4	$ 6.8
Notes Receivable - Fair Value	7.4	6.8
Carrying Value and Fair Value of Other Financial Instruments [Line Items]
Debt Obligations - Carrying Value	2,137.1	2,181.5
Debt Obligations - Fair Value	2,292.0	2,562.2
Convertible obligations [Member]
Carrying Value and Fair Value of Other Financial Instruments [Line Items]
Debt Obligations - Carrying Value	327.9	657.9
Debt Obligations - Fair Value	461.4	992.0
Senior notes [Member]
Carrying Value and Fair Value of Other Financial Instruments [Line Items]
Debt Obligations - Carrying Value	1,784.9	989.6
Debt Obligations - Fair Value	1,806.3	1,016.1
Senior subordinated notes [Member]
Carrying Value and Fair Value of Other Financial Instruments [Line Items]
Debt Obligations - Carrying Value	0	500.0
Debt Obligations - Fair Value	0	520.1
Other debt obligations [Member]
Carrying Value and Fair Value of Other Financial Instruments [Line Items]
Debt Obligations - Carrying Value	24.3	34.0
Debt Obligations - Fair Value	$ 24.3	$ 34.0

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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.

+ Details

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- Definition

Estimated fair value of the debt instrument at the balance-sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 10

+ Details

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- Definition

An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date more than one year from the balance sheet date, net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among myriad other features and characteristics.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 17
-Article 5

+ Details

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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. An amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money at a future date(s).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 3
-Subparagraph b
-Article 5

+ Details

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