Fair Value (Financial Instruments Carried at Other Than Fair Value) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023
Assets
Policy loans	$ 1,256	$ 938
Liabilities
Separate account liabilities	83,489	81,690	$ 81,124
Carrying Value
Assets
Mortgage loans	22,634	22,475
Policy loans	1,256	938
Other invested assets	259	260
Premiums, reinsurance and other receivables	8,053	7,431
Liabilities
Policyholder account balances	31,867	31,362
Long-term debt	835	836
Other liabilities	1,535	1,191
Separate account liabilities	1,243	1,148
Estimated Fair Value
Assets
Mortgage loans	20,513	20,578
Policy loans	1,285	973
Other invested assets	259	260
Premiums, reinsurance and other receivables	8,243	7,578
Liabilities
Policyholder account balances	31,273	30,501
Long-term debt	796	781
Other liabilities	1,535	1,191
Separate account liabilities	1,243	1,148
Estimated Fair Value \| Level 1
Assets
Mortgage loans	0	0
Policy loans	0	0
Other invested assets	0	0
Premiums, reinsurance and other receivables	0	0
Liabilities
Policyholder account balances	0	0
Long-term debt	0	0
Other liabilities	0	0
Separate account liabilities	0	0
Estimated Fair Value \| Level 2
Assets
Mortgage loans	0	0
Policy loans	796	479
Other invested assets	245	245
Premiums, reinsurance and other receivables	132	80
Liabilities
Policyholder account balances	0	0
Long-term debt	25	26
Other liabilities	788	438
Separate account liabilities	1,243	1,148
Estimated Fair Value \| Level 3
Assets
Mortgage loans	20,513	20,578
Policy loans	489	494
Other invested assets	14	15
Premiums, reinsurance and other receivables	8,111	7,498
Liabilities
Policyholder account balances	31,273	30,501
Long-term debt	771	755
Other liabilities	747	753
Separate account liabilities	$ 0	$ 0

Total amount of mortgage loans not valued on a recurring basis as of the balance sheet date.

No definition available.

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- Definition

Fair value portion of other investments not otherwise specified in the taxonomy.

+ References

No definition available.

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- Definition

Fair value portion of the liability of policyholders for deposits held under the terms of insurance contracts.

+ References

No definition available.

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- References

No definition available.

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- Definition

Amount before allowance of loans made to policy and contract holders using their life insurance contracts' cash value or separate accounts as collateral. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums over and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Fair value portion of other liabilities.

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- Definition

Fair value portion of receivables, including, but not limited to, trade account receivables, note receivables, and loan receivables.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Amount of liability for variable contract in which all or portion of contract holder's funds is allocated to specific separate account and supported by assets held in separate account.

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