Investments - Recognized Gains (Losses), net (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Schedule of Investments [Line Items]
Net realized gains on fixed maturity available-for-sale securities	$ 22	$ 20	$ 75	$ 36
Realized gains (losses) on other invested assets	0	(10)	8	(23)
Change in allowance for expected credit losses	1	(11)	7	(35)
Realized gains on certain derivative instruments	138	30	318	39
Unrealized (losses) gains on certain derivative instruments	(141)	16	(34)	21
Change in fair value of reinsurance related embedded derivatives	23	(14)	23	(35)
Change in fair value of other derivatives and embedded derivatives	0	2	3	3
Realized gains on derivatives and embedded derivatives	20	34	310	28
Recognized gains and losses, net	(154)	73	121	(85)
Equity securities
Schedule of Investments [Line Items]
Net realized/unrealized (losses) gains on securities	(193)	(6)	(281)	(63)
Valuation (losses) gains	194	(1)	285	(56)
Preferred securities
Schedule of Investments [Line Items]
Net realized/unrealized (losses) gains on securities	(4)	46	2	(28)
Valuation (losses) gains	$ 1	$ (18)	$ (4)	$ 55

Change In Fair Value Derivatives, Including Other Derivatives

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Equity Securities, FV-NI, Valuation Gain (Loss)

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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), investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

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Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of increase (decrease) in allowance for credit loss on financing receivable.

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Amount of realized and unrealized gain (loss) on investment.

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The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

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Amount of gain (loss) included in earnings for investments classified as other.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

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