Investments - Investments - Net Realized Capital Gains (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Schedule of Investments [Line Items]
Net realized losses	$ (7)	$ (145)
Realized Investment Gains Losses
Schedule of Investments [Line Items]
Equity Securities, FV-NI, Unrealized Gain (Loss)	2	(131)
Not Designated as Hedging Instrument
Schedule of Investments [Line Items]
Translation Adjustment Functional to Reporting Currency, Increase (Decrease), Gross of Tax	(7)	6
Other, net
Schedule of Investments [Line Items]
Other, net	(15)	51
Total Fixed Maturities, AFS
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Realized Gain	17	23
Gross losses on sales of fixed maturities	(39)	(95)
Change in ACL on fixed maturities, AFS	(5)	(12)
Reduction due to intent to sell	0	(3)
Equity Securities [Member]
Schedule of Investments [Line Items]
Equity Securities, FV-NI, Realized Gain (Loss)	50	40
Equity Securities, FV-NI, Unrealized Gain (Loss)	(15)	(147)
Equity securities	35	(107)
Mortgages [Member]
Schedule of Investments [Line Items]
Change in ACL on mortgage loans	$ 0	$ (2)

Amount of increase (decrease) in allowance for credit loss of 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 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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