Fair Value (Financial Instruments Carried at Other Than Fair Value) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Assets
Policy loans	$ 875	$ 1,001
Liabilities
Separate account liabilities	99,668	91,511
Estimated Fair Value
Assets
Mortgage loans	16,291	13,761
Policy loans	983	1,071
Other Investments Fair Value Disclosure	51	77
Premiums, reinsurance and other receivables	2,468	1,532
Liabilities
Policyholder account balances	15,576	13,732
Long-term debt	942	418
Other liabilities	946	377
Separate account liabilities	1,186	1,025
Estimated Fair Value \| Level 1
Assets
Mortgage loans	0	0
Policy loans	0	0
Other Investments Fair Value Disclosure	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	479	619
Other Investments Fair Value Disclosure	39	64
Premiums, reinsurance and other receivables	41	31
Liabilities
Policyholder account balances	0	0
Long-term debt	39	38
Other liabilities	169	54
Separate account liabilities	1,186	1,025
Estimated Fair Value \| Level 3
Assets
Mortgage loans	16,291	13,761
Policy loans	504	452
Other Investments Fair Value Disclosure	12	13
Premiums, reinsurance and other receivables	2,427	1,501
Liabilities
Policyholder account balances	15,576	13,732
Long-term debt	903	380
Other liabilities	777	323
Separate account liabilities	0	0
Carrying Value
Assets
Mortgage loans	15,664	13,596
Policy loans	875	1,001
Other Investments Fair Value Disclosure	51	77
Premiums, reinsurance and other receivables	2,053	1,426
Liabilities
Policyholder account balances	15,474	15,183
Long-term debt	844	434
Other liabilities	943	395
Separate account liabilities	$ 1,186	$ 1,025

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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