Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 129	$ 99	$ 194	$ 186
Other comprehensive income (loss), before tax:
Unrealized gains/losses on securities	498	(218)	1,131	(700)
Other-than-temporary impairments	1	0	1	7
Pension and other postretirement benefits liability	(1)	0	(1)	(1)
Other comprehensive income (loss), before tax	498	(218)	1,131	(694)
Income tax expense (benefit) related to items of other comprehensive income (loss)	105	(40)	236	(148)
Other comprehensive income (loss), after tax	393	(178)	895	(546)
Comprehensive income (loss)	$ 522	$ (79)	$ 1,089	$ (360)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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