Fair Value (Financial Instruments Carried at Other Than Fair Value) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Assets
Policy loans	$ 1,289	$ 1,292
Liabilities
Separate account liabilities	103,184	107,107
Carrying Value
Assets
Mortgage loans	15,746	15,753
Policy loans	1,289	1,292
Other invested assets	93	51
Premiums, reinsurance and other receivables	3,088	2,224
Liabilities
Policyholder account balances	17,651	15,614
Long-term debt	3,979	4,365
Other liabilities	1,136	846
Separate account liabilities	1,207	1,189
Estimated Fair Value
Assets
Mortgage loans	16,720	16,383
Policy loans	2,116	1,578
Other invested assets	93	51
Premiums, reinsurance and other receivables	3,770	2,634
Liabilities
Policyholder account balances	18,843	15,710
Long-term debt	4,169	4,334
Other liabilities	1,136	846
Separate account liabilities	1,207	1,189
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	506	516
Other invested assets	81	39
Premiums, reinsurance and other receivables	64	41
Liabilities
Policyholder account balances	0	0
Long-term debt	4,169	3,334
Other liabilities	480	191
Separate account liabilities	1,207	1,189
Estimated Fair Value \| Level 3
Assets
Mortgage loans	16,720	16,383
Policy loans	1,610	1,062
Other invested assets	12	12
Premiums, reinsurance and other receivables	3,706	2,593
Liabilities
Policyholder account balances	18,843	15,710
Long-term debt	0	1,000
Other liabilities	656	655
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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- Definition

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

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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 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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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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