Investments - Investment Related Gains (Losses) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
AFS fixed maturity securities
Gross realized gains on investment activity	$ 73	$ 164
Gross realized losses on investment activity	(143)	(134)
Net realized investment gains (losses) on AFS securities	(70)	30
Debt Securities, Trading, Gain (Loss)	(69)	(223)
Net recognized investment gains (losses) on equity securities	17	(50)
Derivative losses	(438)	(3,019)
Provision for Loan, Lease, and Other Losses	(8)	(284)
Other gains (losses)	80	(26)
Investment related gains (losses) (related party: 2021 – $(139) and 2020 – $(631); and consolidated variable interest entities: 2021 – $(66) and 2020 – $1)	(488)	(3,572)
Proceeds from Sale of Debt Securities, Available-for-sale	$ 892	$ 1,807

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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