Earnings per Common Share (Tables)

3 Months Ended

Mar. 31, 2015

Earnings Per Share [Abstract]

Computation of basic and diluted earnings per common share

The computation of basic and diluted earnings per common share is presented in the following table.

($ in millions, except per share data)	Three months ended March 31,
	2015		2014
Numerator:
Net income	$	677	$	600
Less: Preferred stock dividends	29		13
Net income available to common shareholders	$	648	$	587
Denominator:
Weighted average common shares outstanding	415.8		446.4
Effect of dilutive potential common shares:
Stock options	4.9		4.4
Restricted stock units (non-participating) and performance stock awards	1.9		2.0
Weighted average common and dilutive potential common shares outstanding	422.6		452.8
Earnings per common share - Basic	$	1.56	$	1.31
Earnings per common share - Diluted	$	1.53	$	1.30