Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 495	$ 210	$ 113
Other comprehensive income (loss), before tax:
Unrealized gains/losses on securities	(897)	387	258
Other-than-temporary impairments	8	(4)	9
Pension and other postretirement benefits liability	(1)	(2)	(1)
Other comprehensive income (loss), before tax	(890)	381	266
Income tax expense (benefit) related to items of other comprehensive income (loss)	(192)	122	93
Other comprehensive income (loss), after tax	(698)	259	173
Comprehensive income (loss)	$ (203)	$ 469	$ 286

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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