Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net Income	$ 1,203.4	$ 1,233.1	$ 1,111.6
Unrealized gain (loss) on cash flow hedge, net of income taxes of ($2.3)	(3.3)	0.0	0.0
Unrealized gain (loss) on available-for-sale securities, net of income taxes of $0.1 and $0.2 and $0.2 for 2015, 2014 and 2013, respectively	0.3	0.4	0.4
Foreign currency translation adjustment, net of income taxes of ($220.0) and ($227.9) and ($62.3) for 2015, 2014 and 2013, respectively	(427.2)	(442.4)	(120.6)
Defined benefit pension and postemployment plans adjustment, net of income taxes of $2.8 and ($15.5) and $14.1 for 2015, 2014 and 2013, respectively	4.2	(23.3)	21.0
Other Comprehensive Income (Loss)	(426.0)	(465.3)	(99.2)
Comprehensive Income	777.4	767.8	1,012.4
Comprehensive Income Attributed To Noncontrolling Interests	80.7	90.4	83.4
Comprehensive Income - Omnicom Group Inc.	$ 696.7	$ 677.4	$ 929.0