Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 34	$ 45
Other comprehensive income (loss), before tax:
Unrealized gains (losses) on securities	(960)	633
Impairments	0	0
Pension and other postretirement benefits liability	0	0
Other comprehensive income (loss), before tax	(960)	633
Income tax expense (benefit) related to items of other comprehensive income (loss)	(201)	131
Other comprehensive income (loss), after tax	(759)	502
Comprehensive income (loss)	$ (725)	$ 547

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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