Changes in Policyholders' Account Balances (Details) - Investment contract reserves: - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Deferred Fixed Annuity
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	$ 575	$ 618	$ 595	$ 656
Premiums received	7	10	19	29
Policy charges	0	0	0	0
Surrenders and withdrawals	(15)	(25)	(50)	(88)
Benefit payments	(7)	(4)	(15)	(9)
Interest credited	5	6	16	17
Balance, end of period	$ 565	$ 605	$ 565	$ 605
Weighted average crediting rate	3.71%	3.64%	3.71%	3.64%
Net amount at risk	$ 0	$ 0	$ 0	$ 0
Cash surrender value	559	599	559	599
Universal life
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	454	456	456	457
Premiums received	8	9	27	28
Policy charges	(10)	(10)	(30)	(30)
Surrenders and withdrawals	(3)	(2)	(9)	(9)
Benefit payments	(1)	(1)	(6)	(4)
Interest credited	5	4	15	14
Balance, end of period	$ 453	$ 456	$ 453	$ 456
Weighted average crediting rate	4.43%	4.36%	4.43%	4.36%
Net amount at risk	$ 3,719	$ 3,865	$ 3,719	$ 3,865
Cash surrender value	$ 426	$ 426	$ 426	$ 426

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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