Fair Value (Financial Instruments Carried at Other Than Fair Value) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Assets
Policy loans	$ 9,334	$ 9,493
Liabilities
Collateral financing arrangement	833	845
Junior subordinated debt securities	3,153	3,153
Separate account liabilities	196,200	199,970
Carrying Value
Assets
Mortgage loans	82,866	83,754
Policy loans	9,334	9,493
Other invested assets	1,167	1,188
Premiums, reinsurance and other receivables	2,948	2,729
Other assets	693	300
Liabilities
Policyholder account balances	127,897	126,458
Long-term debt	14,409	14,492
Collateral financing arrangement	833	845
Junior subordinated debt securities	3,153	3,153
Other liabilities	3,049	2,113
Separate account liabilities	112,606	115,682
Estimated Fair Value
Assets
Mortgage loans	86,894	88,675
Policy loans	11,058	11,598
Other invested assets	1,167	1,188
Premiums, reinsurance and other receivables	3,124	2,978
Other assets	695	301
Liabilities
Policyholder account balances	132,533	134,569
Long-term debt	17,078	18,332
Collateral financing arrangement	699	710
Junior subordinated debt securities	4,478	4,604
Other liabilities	3,670	3,133
Separate account liabilities	112,606	115,682
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
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	0	0
Policy loans	0	0
Other invested assets	814	814
Premiums, reinsurance and other receivables	1,145	908
Other assets	510	111
Liabilities
Policyholder account balances	0	0
Long-term debt	17,078	18,332
Collateral financing arrangement	0	0
Junior subordinated debt securities	4,478	4,604
Other liabilities	1,478	527
Separate account liabilities	112,606	115,682
Estimated Fair Value \| Level 3
Assets
Mortgage loans	86,894	88,675
Policy loans	11,058	11,598
Other invested assets	353	374
Premiums, reinsurance and other receivables	1,979	2,070
Other assets	185	190
Liabilities
Policyholder account balances	132,533	134,569
Long-term debt	0	0
Collateral financing arrangement	699	710
Junior subordinated debt securities	0	0
Other liabilities	2,192	2,606
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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