Transactions with Affiliates - Comprehensive Income (Loss) Transactions with Affiliates (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Insurance premiums	$ 6,352	$ 8,584	$ 11,207
Net investment income	5,088	5,712	5,274
Realized gain (loss)	276	(4,934)	418
Other revenues	572	697	658
Benefits	2,100	5,028	8,203
Market risk benefit (gain) loss	938	1,135	(296)
Policyholder liability remeasurement (gain) loss	(20)	(167)	2,445
Interest and debt expense	185	190	137
Related Party
Related Party Transaction [Line Items]
Other revenues	(475)	(171)	0
Premiums received on assumed (paid on ceded) reinsurance contracts \| Related Party
Related Party Transaction [Line Items]
Insurance premiums	(5,427)	(498)	(421)
Fees for management of general account \| Related Party
Related Party Transaction [Line Items]
Net investment income	(97)	(156)	(140)
Net investment income on ceded funds withheld treaties \| Related Party
Related Party Transaction [Line Items]
Net investment income	(260)	(238)	(161)
Net investment income on inter-company notes \| Related Party
Related Party Transaction [Line Items]
Net investment income	63	65	40
Interest and debt expense	146	148	120
Net investment income associated with cash management agreement \| Related Party
Related Party Transaction [Line Items]
Net investment income	59	11	0
Ceded reinsurance contracts \| Related Party
Related Party Transaction [Line Items]
Benefits	(5,844)	(507)	(247)
Commissions and other expenses	(76)	(13)	(26)
Ceded reinsurance contracts \| Reinsurance-related settlements \| Related Party
Related Party Transaction [Line Items]
Realized gain (loss)	305	1,717	(1,068)
Ceded reinsurance contracts \| Other gains (losses) \| Related Party
Related Party Transaction [Line Items]
Realized gain (loss)	289	(9)	631
Amortization of deferred gain (loss) on reinsurance contracts \| Related Party
Related Party Transaction [Line Items]
Amortization of deferred gain (loss) on business sold through reinsurance	167	17	3
Interest credited on assumed reinsurance contracts (interest recoveries on ceded reinsurance contracts) \| Related Party
Related Party Transaction [Line Items]
Interest credited	(229)	12	47
Market risk benefit (gain) loss on ceded reinsurance contracts \| Other gains (losses) \| Related Party
Related Party Transaction [Line Items]
Market risk benefit (gain) loss	1,740	1,129	3,543
Policyholder liability remeasurement (gain) loss on ceded reinsurance contracts \| Other gains (losses) \| Related Party
Related Party Transaction [Line Items]
Policyholder liability remeasurement (gain) loss	209	0	(321)
Amortization of deferred loss on reinsurance contracts \| Related Party
Related Party Transaction [Line Items]
Commissions and other expenses	5	0	0
Service agreement payments (receipts) \| Related Party
Related Party Transaction [Line Items]
Commissions and other expenses	$ (7)	$ (17)	$ (53)

The amortization of net deferred gain (loss) on indemnity reinsurance transactions.

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Amount of realized gain (loss) on investment in debt and equity securities.

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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