Other Comprehensive Income (Tables)

12 Months Ended

Dec. 31, 2019

Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]

Other comprehensive income (loss) on a pre-tax and after-tax basis

Components of other comprehensive income (loss) on a pre-tax and after-tax basis
	For the years ended December 31,
($ in millions)	2019									2018								2017
	Pre-tax			Tax			After-tax			Pre-tax			Tax		After-tax			Pre-tax			Tax			After-tax
Unrealized net holding gains and losses arising during the period, net of related offsets	$	2,807		$	(592	)	$	2,215		$	(1,142	)	$	241	$	(901	)	$	866		$	(304	)	$	562
Less: reclassification adjustment of realized capital gains and losses	413			(87		)	326			(186		)	39		(147		)	374			(131		)	243
Unrealized net capital gains and losses	2,394			(505		)	1,889			(956		)	202		(754		)	492			(173		)	319
Unrealized foreign currency translation adjustments	(13		)	3			(10		)	(61		)	13		(48		)	69			(24		)	45
Unamortized pension and other postretirement prior service credit	(59		)	12			(47		)	(77		)	18		(59		)	(80		)	28			(52		)
Other comprehensive income (loss)	$	2,322		$	(490	)	$	1,832		$	(1,094	)	$	233	$	(861	)	$	481		$	(169	)	$	312