Earnings Per Share Basic and Diluted Earnings Per Common Share Available to IPG Common Stockholders (Tables)

12 Months Ended

Dec. 31, 2015

Earnings Per Share [Abstract]

Basic and Diluted Earnings Per Common Share Available to IPG Common Stockholders

The following sets forth basic and diluted earnings per common share available to IPG common stockholders.

	Years ended December 31,
	2015		2014		2013
Net income available to IPG common stockholders - basic	$	454.6	$	477.1	$	259.2
Adjustments: Effect of dilutive securities
Interest on 4.75% Notes 1	0.0		0.0		0.8
Net income available to IPG common stockholders - diluted	$	454.6	$	477.1	$	260.0
Weighted-average number of common shares outstanding - basic	408.1		419.2		421.1
Add: Effect of dilutive securities
Restricted stock, stock options and other equity awards	7.6		6.2		5.2
4.75% Notes 1	0.0		0.0		3.3
Weighted-average number of common shares outstanding - diluted	415.7		425.4		429.6
Earnings per share available to IPG common stockholders - basic	$	1.11	$	1.14	$	0.62
Earnings per share available to IPG common stockholders - diluted	$	1.09	$	1.12	$	0.61

1 We retired all of our outstanding 4.75% Convertible Senior Notes due 2023 (the "4.75% Notes") in March 2013. For purposes of calculating diluted earnings per share for 2013, the potentially dilutive shares are pro-rated based on the period in which they were outstanding.