Fair Value (Financial Instruments Carried at Other Than Fair Value) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Assets
Policy loans	$ 1,106	$ 1,093
Liabilities
Separate account liabilities	110,156	105,346
Estimated Fair Value
Assets
Mortgage loans	10,768	9,298
Policy loans	1,185	1,177
Real estate joint ventures	22	44
Other limited partnership interests	28	42
Loans and Leases Receivable, Related Parties	0	1,090
Premiums, reinsurance and other receivables	1,909	2,815
Liabilities
Policyholder account balances	15,760	17,259
Long-term debt	42	2,117
Other liabilities	461	256
Separate account liabilities	1,206	1,110
Estimated Fair Value \| Level 1
Assets
Mortgage loans	0	0
Policy loans	0	0
Real estate joint ventures	0	0
Other limited partnership interests	0	0
Loans and Leases Receivable, Related Parties	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	746	746
Real estate joint ventures	0	0
Other limited partnership interests	0	0
Loans and Leases Receivable, Related Parties	0	1,090
Premiums, reinsurance and other receivables	126	834
Liabilities
Policyholder account balances	0	0
Long-term debt	42	2,117
Other liabilities	93	90
Separate account liabilities	1,206	1,110
Estimated Fair Value \| Level 3
Assets
Mortgage loans	10,768	9,298
Policy loans	439	431
Real estate joint ventures	22	44
Other limited partnership interests	28	42
Loans and Leases Receivable, Related Parties	0	0
Premiums, reinsurance and other receivables	1,783	1,981
Liabilities
Policyholder account balances	15,760	17,259
Long-term debt	0	0
Other liabilities	368	166
Separate account liabilities	0	0
Carrying Value
Assets
Mortgage loans	10,525	9,154
Policy loans	1,106	1,093
Real estate joint ventures	5	12
Other limited partnership interests	36	44
Loans and Leases Receivable, Related Parties	0	1,100
Premiums, reinsurance and other receivables	1,556	2,363
Liabilities
Policyholder account balances	15,626	16,043
Long-term debt	35	1,881
Other liabilities	459	256
Separate account liabilities	$ 1,206	$ 1,110

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

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The fair value portion of investments in other limited partnership interests.

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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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For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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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The book value of investments in real estate joint ventures including direct and indirect investments.

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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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