Investments - Recognized Gains (Losses), net (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Schedule of Investments [Line Items]
Net realized losses on fixed maturity available-for-sale securities	$ (50)	$ (36)
Realized losses on other invested assets	(5)	(1)
Change in allowance for expected credit losses	(4)	(4)
Realized (losses) gains on certain derivative instruments	(89)	50
Unrealized gains (losses) on certain derivative instruments	147	(358)
Change in fair value of other derivatives and embedded derivatives	2	(3)
Realized gains (losses) on derivatives and embedded derivatives	41	(189)
Recognized gains and losses, net	5	(469)
Reinsurance related embedded derivatives, included in accounts payable and accrued liabilities
Schedule of Investments [Line Items]
Change in fair value of reinsurance related embedded derivatives	(19)	122
Equity securities
Schedule of Investments [Line Items]
Net realized/unrealized (losses) gains on securities	33	(148)
Valuation losses	46	166
Preferred securities
Schedule of Investments [Line Items]
Net realized/unrealized (losses) gains on securities	(10)	(91)
Valuation losses	$ 35	$ 90

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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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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