Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 2,085	$ 1,807	$ (3,131)
Other comprehensive income (loss):
Changes in net unrealized gain on securities	1,660	(2,180)	655
Changes in OTTI losses recognized in other comprehensive income (OCI)	1	(1)	0
Changes in net gain on cash flow hedging instruments	14	(25)	(58)
Changes in foreign currency translation adjustments	4	(8)	28
Changes in pension and other postretirement plan adjustments	(48)	(23)	375
OCI, net of tax	1,631	(2,237)	1,000
Comprehensive income (loss)	$ 3,716	$ (430)	$ (2,131)

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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