Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 273	$ 630
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Changes in net unrealized gain on fixed maturities	(1,057)	679
Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, after Tax	1
Other Comprehensive Loss, Held-to-maturity Security, OTTI, after Tax and Adjustments		(1)
Changes in net gain on cash flow hedging instruments	(44)	(5)
Changes in foreign currency translation adjustments	(8)	1
Changes in pension and other postretirement plan adjustments	(11)	(8)
OCI, net of tax	(1,009)	694
Comprehensive income (loss)	$ (736)	$ 1,324

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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