Changes in Policyholders' Account Balances (Details) - Investment contract reserves: - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Deferred Fixed Annuity
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	$ 734	$ 763
Premiums received	10	6
Policy charges	0	0
Surrenders and withdrawals	(36)	(12)
Benefit payments	(3)	(6)
Interest credited	6	5
Balance, end of period	$ 711	$ 756
Weighted average crediting rate	3.36%	2.95%
Net amount at risk	$ 0	$ 0
Cash surrender value	706	752
Universal life
Policyholder Account Balance [Roll Forward]
Balance, beginning of period	457	454
Premiums received	11	11
Policy charges	(10)	(10)
Surrenders and withdrawals	(3)	(3)
Benefit payments	(2)	(1)
Interest credited	5	5
Balance, end of period	$ 458	$ 456
Weighted average crediting rate	4.26%	4.25%
Net amount at risk	$ 4,064	$ 4,172
Cash surrender value	$ 424	$ 421

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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- Definition

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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