Quarterly Results (unaudited)

12 Months Ended

Dec. 31, 2018

Quarterly Financial Information Disclosure [Abstract]

Quarterly Results (unaudited)

Note 21 Quarterly Results (unaudited)

As adjusted	First Quarter				Second Quarter					Third Quarter				Fourth Quarter
($ in millions, except per share data)	2018		2017		2018		2017			2018		2017		2018			2017
Revenues	$	9,770	$	9,644	$	10,099	$	9,813		$	10,465	$	9,888	$	9,481		$	10,062
Net income (loss) applicable to common shareholders	977		785		678		549			942		810		(585		)	1,294
Earnings per common share - Basic	2.76		2.15		1.94		1.51			2.72		2.24		(1.71		)	3.62
Earnings per common share - Diluted	2.71		2.11		1.91		1.49			2.68		2.21		(1.71		)	3.56
Impact of change	First Quarter				Second Quarter					Third Quarter				Fourth Quarter
($ in millions, except per share data)	2018		2017		2018		2017			2018		2017		2018			2017
Revenues	$	—	$	—	$	—	$	—		$	—	$	—	$	—		$	—
Net income (loss) applicable to common shareholders	31		119		41		(1		)	109		173		(273		)	74
Earnings per common share - Basic	0.09		0.33		0.12		—			0.31		0.48		(0.80		)	0.21
Earnings per common share - Diluted	0.08		0.32		0.11		—			0.31		0.47		(0.80		)	0.21