Fair Value (Financial Instruments Carried at Other Than Fair Value) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Assets
Policy loans	$ 8,800	$ 8,788
Liabilities
Collateral financing arrangement	590	637
Junior subordinated debt securities	3,162	3,161
Separate account liabilities	141,003	144,634
Carrying Value
Assets
Mortgage loans (1)	91,458	92,506
Policy loans	8,800	8,788
Other invested assets	1,237	919
Premiums, reinsurance and other receivables	5,192	5,182
Other assets	252	268
Liabilities
Policyholder account balances	138,419	138,233
Long-term debt	15,946	15,516
Collateral financing arrangement	590	637
Junior subordinated debt securities	3,162	3,161
Other liabilities	10,646	10,556
Separate account liabilities	71,713	75,705
Estimated Fair Value
Assets
Mortgage loans (1)	86,188	87,753
Policy loans	9,443	9,516
Other invested assets	1,237	919
Premiums, reinsurance and other receivables	5,178	5,191
Other assets	254	266
Liabilities
Policyholder account balances	133,040	134,025
Long-term debt	15,658	15,621
Collateral financing arrangement	510	551
Junior subordinated debt securities	3,589	3,552
Other liabilities	10,271	10,260
Separate account liabilities	71,713	75,705
Estimated Fair Value \| Level 1
Assets
Mortgage loans (1)	0	0
Policy loans	0	0
Other invested assets	0	0
Premiums, reinsurance and other receivables	0	0
Other assets	0	0
Liabilities
Policyholder account balances	0	0
Long-term debt	0	0
Collateral financing arrangement	0	0
Junior subordinated debt securities	0	0
Other liabilities	0	0
Separate account liabilities	0	0
Estimated Fair Value \| Level 2
Assets
Mortgage loans (1)	0	0
Policy loans	0	0
Other invested assets	714	714
Premiums, reinsurance and other receivables	863	791
Other assets	84	82
Liabilities
Policyholder account balances	0	0
Long-term debt	15,658	15,621
Collateral financing arrangement	0	0
Junior subordinated debt securities	3,589	3,552
Other liabilities	1,113	609
Separate account liabilities	71,713	75,705
Estimated Fair Value \| Level 3
Assets
Mortgage loans (1)	86,188	87,753
Policy loans	9,443	9,516
Other invested assets	523	205
Premiums, reinsurance and other receivables	4,315	4,400
Other assets	170	184
Liabilities
Policyholder account balances	133,040	134,025
Long-term debt	0	0
Collateral financing arrangement	510	551
Junior subordinated debt securities	0	0
Other liabilities	9,158	9,651
Separate account liabilities	$ 0	$ 0

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

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

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

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Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments.

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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.

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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 assets.

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Fair value portion of other liabilities.

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

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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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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