Condensed Consolidated Statements of Income (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Revenue	$ 3,406.6	$ 3,380.9	$ 10,274.8	$ 10,019.6
Operating Expenses	3,019.3	3,007.5	9,018.6	8,835.9
Operating Income	387.3	373.4	1,256.2	1,183.7
Interest Expense	47.8	39.8	130.3	118.6
Interest Income	7.5	7.9	26.0	26.8
Income Before Income Taxes and Income From Equity Method Investments	347.0	341.5	1,151.9	1,091.9
Income Tax Expense	118.7	117.1	389.9	349.0
Income From Equity Method Investments	5.3	4.5	11.9	10.3
Net Income	233.6	228.9	773.9	753.2
Less: Net Income Attributed To Noncontrolling Interests	29.7	25.2	82.7	72.5
Net Income - Omnicom Group Inc.	$ 203.9	$ 203.7	$ 691.2	$ 680.7
Net Income Per Share - Omnicom Group Inc.:
Basic	$ 0.75	$ 0.73	$ 2.51	$ 2.41
Diluted	$ 0.74	$ 0.72	$ 2.49	$ 2.37
Dividends Declared Per Common Share	$ 0.30	$ 0.25	$ 0.90	$ 0.75