Consolidated Statements of Stockholders' Equity (USD $) In Millions	Total	Preferred Stock	Common Stock	Additional Paid-In Capital	Retained Earnings (Accumulated Deficit)	Accumulated Other Comprehensive Loss, Net of Tax	Treasury Stock	Total IPG Stockholders' Equity	Noncontrolling Interests
Beginning balance at Dec. 31, 2010	$ 2,566.9	$ 221.5	$ 47.5	$ 2,456.8	$ (63.7)	$ (119.0)	$ (14.1)	$ 2,529.0	$ 37.9
Beginning balance, shares at Dec. 31, 2010			489.5
Net income	55.7				59.4			59.4	(3.7)
Other comprehensive income	72.8					72.4		72.4	0.4
Reclassifications related to redeemable noncontrolling interests	10.2								10.2
Noncontrolling interest transactions	(3.1)								(3.1)
Distributions to noncontrolling interests	(10.7)								(10.7)
Change in redemption value of redeemable noncontrolling interests	(10.3)			(10.3)				(10.3)
Repurchase of common stock	(139.0)						(139.0)	(139.0)
Common stock dividends	(56.8)			(56.8)				(56.8)
Preferred stock dividends	(5.8)			(5.8)				(5.8)
Stock-based compensation, shares			3.0
Stock-based compensation	28.7		0.7	28.0				28.7
Exercise of stock options, shares			1.2
Exercise of stock options	11.8		0.1	11.7				11.8
Shares withheld for taxes, shares			(2.3)
Shares withheld for taxes	(25.3)		(0.2)	(25.1)				(25.3)
Other	0.4			(0.5)				(0.5)	0.9
Ending balance at Jun. 30, 2011	2,495.5	221.5	48.1	2,398.0	(4.3)	(46.6)	(153.1)	2,463.6	31.9
Ending balance, shares at Jun. 30, 2011			491.4
Beginning balance at Dec. 31, 2011	2,497.3	221.5	48.2	2,427.5	405.1	(225.7)	(414.9)	2,461.7	35.6
Beginning balance, shares at Dec. 31, 2011			491.4
Net income	59.8				58.9			58.9	0.9
Other comprehensive income	56.3					57.4		57.4	(1.1)
Reclassifications related to redeemable noncontrolling interests	15.7			12.0				12.0	3.7
Noncontrolling interest transactions	(0.8)								(0.8)
Distributions to noncontrolling interests	(9.0)								(9.0)
Change in redemption value of redeemable noncontrolling interests	3.1				3.1			3.1
Repurchase of common stock	(118.1)						(118.1)	(118.1)
Common stock dividends	(52.3)				(52.3)			(52.3)
Preferred stock dividends	(5.8)				(5.8)			(5.8)
Stock-based compensation, shares			1.7
Stock-based compensation	21.4		0.6	20.8				21.4
Exercise of stock options, shares			0.8
Exercise of stock options	7.8		0.1	7.7				7.8
Shares withheld for taxes, shares			(2.0)
Shares withheld for taxes	(23.1)		(0.2)	(22.9)				(23.1)
Other	0.1			1.8	(0.8)			1.0	(0.9)
Ending balance at Jun. 30, 2012	$ 2,452.4	$ 221.5	$ 48.7	$ 2,446.9	$ 408.2	$ (168.3)	$ (533.0)	$ 2,424.0	$ 28.4
Ending balance, shares at Jun. 30, 2012			491.9