Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2017

Earnings Per Share

Schedule Of Earnings Per Share Basic And Diluted [Table Text Block]

The following table provides the calculation of earnings per share and the reconciliation of earnings per share and earnings per diluted share for the years ended December 31:
		2017			2016			2015
			Average	Per Share		Average	Per Share		Average	Per Share
($ in millions, except per share data)		Income	Shares	Amount	Income	Shares	Amount	Income	Shares	Amount
Earnings Per Share:
Net income available to common shareholders		2,119			1,489			1,637
Less: Income allocated to participating securities		23			15			15
Net income allocated to common shareholders	$	2,096	728	2.88	1,474	757	1.95	1,622	799	2.03
Earnings Per Diluted Share:
Net income available to common shareholders	$	2,119			1,489			1,637
Effect of dilutive securities:
Stock-based awards		-	13		-	7		-	9
Net income available to common shareholders		2,119			1,489			1,637
plus assumed conversions
Less: Income allocated to participating securities		22			15			15
Net income allocated to common shareholders
plus assumed conversions	$	2,097	741	2.83	1,474	764	1.93	1,622	808	2.01