Accumulated Other Comprehensive Income (Loss) (Details) (Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Noncontrolling Interest [Line Items]
Accumulated translation adjustment included in noncontrolling interest	$ (50.3)	$ (24.4)
Accumulated Other Comprehensive Income Loss (Textual) [Abstract]
Tax on unrealized holding gains (losses) on investments	0.1	7.3
Tax on unrealized holding gains (losses) on foreign currency forward contracts	3.6	1.3
Noncontrolling Interest [Member]
Noncontrolling Interest [Line Items]
Accumulated translation adjustment included in noncontrolling interest	$ 5.1	$ 0.2

Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Reference 7: http://www.xbrl.org/2003/role/presentationRef

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Reference 9: http://www.xbrl.org/2003/role/presentationRef

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+ Details