Earnings Per Share Data

9 Months Ended

Sep. 30, 2012

Earnings Per Share [Abstract]

Earnings Per Share Data

Earnings Per Share Data

Basic earnings per common share is computed by dividing net income available to common stockholders by the weighted-average number of common shares outstanding for the period. Diluted earnings per share adjusts basic earnings per common share for the effects of potentially dilutive common shares, if the effect is not anti-dilutive. Potentially dilutive common shares include the dilutive effects of shares issuable under the Stock Option and Performance Award Plans and shares issuable upon the conversion of preferred stock to common stock. During the first quarter of 2011, the Company converted all of the remaining outstanding Cumulative Convertible Perpetual Preferred Stock, Series D, into 6,999,887 shares of common stock.

The following table reconciles the basic earnings per share computation to the diluted earnings per share computation (in millions, except share and per share amounts):

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2012		2011		2012		2011
Net income available to common stockholders for purposes of computing basic earnings per share	$	90.0	$	99.8	$	285.3	$	233.1
Effect of dividends on conversion of convertible preferred stock	—		—		—		1.3
Net income available to common stockholders for purposes of computing diluted earnings per share	$	90.0	$	99.8	$	285.3	$	234.4
Weighted-average number of shares outstanding (in thousands):
Basic shares	109,739		109,515		109,684		107,752
Effect of dilution	388		347		377		2,052
Diluted shares	110,127		109,862		110,061		109,804
Earnings per share:
Basic earnings per share	$	0.82	$	0.91	$	2.60	$	2.16
Diluted earnings per share	$	0.82	$	0.91	$	2.59	$	2.13
Potentially dilutive shares excluded from the calculation (in thousands):
Stock options excluded as their inclusion would be anti-dilutive	—		121		81		97