Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 99	$ (26)	$ 186	$ 28
Other comprehensive income (loss), before tax:
Unrealized gains/losses on securities	(218)	205	(700)	284
Other-than-temporary impairments	0	0	7	2
Pension and other postretirement benefits liability	0	(1)	(1)	(1)
Other comprehensive income (loss), before tax	(218)	204	(694)	285
Income tax expense (benefit) related to items of other comprehensive income (loss)	(40)	71	(148)	99
Other comprehensive income (loss), after tax	(178)	133	(546)	186
Comprehensive income (loss)	$ (79)	$ 107	$ (360)	$ 214

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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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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