Earnings Per Share

12 Months Ended

Dec. 31, 2013

Earnings Per Share [Abstract]

Earnings Per Share

Earnings per Share

We compute basic earnings per share by dividing net income available to our common shareholders by the weighted average number of shares of our common stock outstanding. We appropriately weighted shares issued or reacquired during the year for the portion of the year that they were outstanding. Our diluted earnings per share reflect the impacts of our potentially dilutive securities, which include our convertible preferred stock and our equity compensation awards.

The following table shows the computation of our basic and diluted net income per common share for the years ending December 31 (in millions, except per share amounts):

	2013		2012		2011
Numerator:
Net income	$	169.3	$	137.3	$	110.8
Denominator:
Denominator for basic earnings per share — weighted average shares	46.4		46.8		46.4
Effect of dilutive securities
Equity compensation plans	0.7		0.7		0.7
Convertible preferred stock	—		0.1		0.1
Weighted average shares outstanding - diluted	47.1		47.6		47.2
Basic earnings per share	$	3.64	$	2.93	$	2.39
Diluted earnings per share	$	3.59	$	2.88	$	2.35