Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 535	$ 432	$ 1,537	$ 1,611
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Changes in net unrealized gain on securities	401	(171)	1,744	(2,164)
Changes in OTTI losses recognized in other comprehensive income	0	1	(1)	1
Changes in net gain on cash flow hedging instruments	6	(5)	22	(37)
Changes in foreign currency translation adjustments	(4)	1	0	(4)
Changes in pension and other postretirement plan adjustments	9	10	26	29
OCI, net of tax	412	(166)	1,793	(2,177)
Comprehensive income (loss)	$ 947	$ 266	$ 3,330	$ (566)

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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