Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2011

Earnings Per Share [Abstract]

Computation of basic and diluted earnings per share

	Years Ended December 31
	2011		2010		2009
	(in millions except for per
	share amounts)
Basic earnings per share:
Net income	$	1,678	$	2,174	$	2,183
Weighted average shares outstanding		289.3		319.2		350.1
Basic earnings per share	$	5.80	$	6.81	$	6.24
Diluted earnings per share:
Net income	$	1,678	$	2,174	$	2,183
Weighted average shares outstanding		289.3		319.2		350.1
Additional shares from assumed issuance of shares under stock-based compensation awards		2.1		2.4		2.9
Weighted average shares and potential shares assumed outstanding for computing diluted earnings per share		291.4		321.6		353.0
Diluted earnings per share	$	5.76	$	6.76	$	6.18