Goodwill and Other Intangible Assets and Liabilities (Estimated Amortization Expense Relating to Intangible Assets) (Details) (USD $) In Millions	6 Months Ended
Jun. 30, 2011
Goodwill and Other Intangible Assets and Liabilities
Estimated amortization expense for 2011 (remaining six months)	$ 9.6
Estimated amortization expense for 2012	19.2
Estimated amortization expense for 2013	18.3
Estimated amortization expense for 2014	18.3
Estimated amortization expense for 2015	6.4
Estimated amortization expense for 2016	6.4
Total	$ 78.2

Goodwill and Other Intangible Assets and Liabilities [Abstract]

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- Definition

The aggregate estimated amortization expense for succeeding fiscal years for intangible assets subject to amortization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 45
-Subparagraph a(3)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275

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The amount of amortization expense expected to be recognized during the remainder of the current fiscal year.

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The amount of amortization expense expected to be recognized during year five of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year one of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

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