Investments - Investment Gains (Losses) Net (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule of Investments [Line Items]
Net realized gains (losses) on fixed maturity available-for-sale securities	$ 111	$ 102	$ (6)
Realized gains (losses) on other invested assets	8	(25)	(13)
Change in allowance for expected credit losses	8	(37)	0
Realized gains on certain derivative instruments	456	76	0
Unrealized gains on certain derivative instruments	159	161	0
Change in fair value of reinsurance related embedded derivatives	34	(53)	0
Change in fair value of other derivatives and embedded derivatives	6	8	0
Realized gains on derivatives and embedded derivatives	655	192	0
Recognized gains and losses, net	334	488	318
Equity securities
Schedule of Investments [Line Items]
Net realized/unrealized gains (losses) on equity and preferred equity securities	(434)	241	309
Valuation gains (losses)	(436)	248	299
Preferred securities
Schedule of Investments [Line Items]
Net realized/unrealized gains (losses) on equity and preferred equity securities	(14)	15	28
Valuation gains (losses)	$ (14)	$ (40)	$ 17

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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