Accrued Liabilities (Details) (USD $) In Millions	3 Months Ended
	Jun. 30, 2011	Dec. 31, 2010
Accrued Liabilities [Abstract]
Media and production expenses	$ 2,249.2	$ 2,332.2
Salaries, benefits and related expenses	365.2	470.0
Office and related expenses	54.3	62.0
Acquisition obligations	8.5	63.5
Interest	40.8	41.5
Professional fees	17.9	24.6
Other	113.5	118.9
Total accrued liabilities	2,849.4	3,112.7
Payments related to transactions with consolidated subsidiaries where we have increased our ownership interests	32.9
Deferred payments relating to a prior-year acquisition	$ 31.8