Fair Value Impairment of Indefinite-lived Intangible Assets Measured at Fair Value on a Nonrecurring Basis (Details) (Change in Fair Value from Asset Impairment [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011
Change in Fair Value from Asset Impairment [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impairment of intangible assets, finite-lived	$ 1.6