Changes in Policyholders' Account Balances (Details) - Investment contract reserves: - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Deferred Fixed Annuity
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	$ 595	$ 656
Premiums received	4	9
Policy charges	0	0
Surrenders and withdrawals	(17)	(37)
Benefit payments	(5)	(3)
Interest credited	5	6
Balance, end of period	$ 582	$ 631
Weighted average crediting rate	3.68%	3.55%
Net amount at risk	$ 0	$ 0
Cash surrender value	575	625
Universal life
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	456	457
Premiums received	10	10
Policy charges	(10)	(10)
Surrenders and withdrawals	(3)	(4)
Benefit payments	(1)	(2)
Interest credited	5	5
Balance, end of period	$ 457	$ 456
Weighted average crediting rate	4.40%	4.33%
Net amount at risk	$ 3,801	$ 3,908
Cash surrender value	$ 428	$ 425

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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