Fair Value (Financial Instruments Carried at Other Than Fair Value) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Assets
Policy loans	$ 967	$ 1,001
Liabilities
Separate account liabilities	97,924	91,511
Carrying Value
Assets
Mortgage loans	14,413	13,596
Policy loans	967	1,001
Other invested assets	63	77
Premiums, reinsurance and other receivables	1,595	1,426
Liabilities
Policyholder account balances	15,139	15,183
Long-term debt	845	434
Other liabilities	902	395
Separate account liabilities	1,134	1,025
Estimated Fair Value
Assets
Mortgage loans	14,730	13,761
Policy loans	1,040	1,071
Other invested assets	63	77
Premiums, reinsurance and other receivables	1,801	1,532
Liabilities
Policyholder account balances	14,204	13,732
Long-term debt	841	418
Other liabilities	902	377
Separate account liabilities	1,134	1,025
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	585	619
Other invested assets	50	64
Premiums, reinsurance and other receivables	117	31
Liabilities
Policyholder account balances	0	0
Long-term debt	39	38
Other liabilities	552	54
Separate account liabilities	1,134	1,025
Estimated Fair Value \| Level 3
Assets
Mortgage loans	14,730	13,761
Policy loans	455	452
Other invested assets	13	13
Premiums, reinsurance and other receivables	1,684	1,501
Liabilities
Policyholder account balances	14,204	13,732
Long-term debt	802	380
Other liabilities	350	323
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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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 contracts that meet specified criteria that are backed by assets held in separate accounts and carried at the fair value of those assets.

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