Changes in Policyholders' Account Balances (Details) - Investment contract reserves - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Deferred Fixed Annuity
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	$ 734	$ 763	$ 761
Premiums received	44	29	44
Policy charges	0	0	0
Surrenders and withdrawals	(130)	(62)	(47)
Benefit payments	(14)	(18)	(17)
Interest credited	22	22	22
Balance, end of period	$ 656	$ 734	$ 763
Weighted average crediting rate	3.51%	3.36%	2.88%
Net amount at risk	$ 0	$ 0	$ 0
Cash surrender value	651	729	757
Universal Life
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	457	454	451
Premiums received	39	39	39
Policy charges	(39)	(39)	(38)
Surrenders and withdrawals	(13)	(11)	(10)
Benefit payments	(6)	(5)	(7)
Interest credited	19	19	19
Balance, end of period	$ 457	$ 457	$ 454
Weighted average crediting rate	4.30%	4.27%	4.25%
Net amount at risk	$ 3,949	$ 4,082	$ 4,198
Cash surrender value	$ 426	$ 424	$ 419

Amount of cash to be paid to policyholder upon termination and surrender of long-duration contract issued by insurance entity.

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Amount of interest expense for allocation to policyholder account balance.

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Amount of cash outflow to policyholder account balance from benefit payment.

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Amount of guaranteed benefit in excess of current account balance of policyholder account balance.

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Amount of decrease in liability for policyholder account balance from policy charge.

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Amount of cash inflow to policyholder account balance from premium received.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of decrease in liability for policyholder account balance from contract redemption and withdrawal of funds.

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Weighted-average crediting rate for liability for policyholder account balance, calculated at a point in time.

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Amount due to policyholder. Includes, but is not limited to, unpaid policy dividend, retrospective refund, and undistributed earnings on participating business. Excludes future policy benefit and claim expense.

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