Earnings Per Share and Equity (Tables)

9 Months Ended

Sep. 30, 2015

Earnings Per Share [Abstract]

Reconciliation of basic and diluted earnings per share

The following table sets forth the components of basic and diluted earnings per share and shows the effect of these stock options, performance share awards and restricted stock on the weighted average number of shares outstanding (in millions) used in calculating diluted earnings per share: 

	Three Months Ended September 30,				Nine Months Ended September 30,
	2015		2014		2015		2014
Net income attributable to common shareholders	$	629	$	993	$	1,959	$	1,604
Average common shares outstanding — basic	913		861		879		860
Potentially dilutive effect of stock options, performance share awards and restricted stock	2		2		4		3
Average common shares outstanding — diluted	915		863		883		863