Changes in Policyholders' Account Balances (Details) - Investment contract reserves: - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Deferred Fixed Annuity
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	$ 656	$ 734
Premiums received	9	10
Policy charges	0	0
Surrenders and withdrawals	(37)	(36)
Benefit payments	(3)	(3)
Interest credited	6	6
Balance, end of period	$ 631	$ 711
Weighted average crediting rate	3.55%	3.36%
Net amount at risk	$ 0	$ 0
Cash surrender value	625	706
Universal life
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	457	457
Premiums received	10	11
Policy charges	(10)	(10)
Surrenders and withdrawals	(4)	(3)
Benefit payments	(2)	(2)
Interest credited	5	5
Balance, end of period	$ 456	$ 458
Weighted average crediting rate	4.33%	4.26%
Net amount at risk	$ 3,908	$ 4,064
Cash surrender value	$ 425	$ 424

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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