Intangible Assets and Goodwill (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Intangible Assets and Goodwill
Amortization expense	$ 15.8	$ 8.6	$ 5.8
Annual amortization for intangible assets
2013	15.3
2014	14.9
2015	14.3
2016	14.1
2017	14.1
Thereafter	80.0
Total estimated amortization expenses	$ 152.7

Aggregate amount of intangible asset amortization recognized as expense during the period.

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-Name Statement of Financial Accounting Standard (FAS)

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

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The amount of amortization expense expected to be recognized for the remainder of the finite-lived intangible asset useful life after the fifth succeeding fiscal year.

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No definition available.

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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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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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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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