Fair Value (Financial Instruments Carried at Other Than Fair Value) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Assets
Policy loans	$ 11,618us-gaap_LoansInsurancePolicy	$ 11,764us-gaap_LoansInsurancePolicy
Liabilities
Collateral financing arrangements	4,196us-gaap_SecuredDebt	4,196us-gaap_SecuredDebt
Junior subordinated debt securities	3,193us-gaap_JuniorSubordinatedNotes	3,193us-gaap_JuniorSubordinatedNotes
Separate account liabilities	316,994us-gaap_SeparateAccountsLiability	317,201us-gaap_SeparateAccountsLiability
Estimated Fair Value [Member]
Assets
Mortgage loans	62,554	57,924
Policy loans	13,934	13,206
Real estate joint ventures	139	169
Other limited partnership interests	906	1,109
Other invested assets	562	844
Premiums, reinsurance and other receivables	3,157	3,110
Other assets	243	352
Liabilities
PABs	139,359	144,631
Long-term debt	18,357	18,564
Collateral financing arrangements	3,961	3,984
Junior subordinated debt securities	4,173	3,789
Other liabilities	2,546	2,240
Separate account liabilities	116,665	117,562
Estimated Fair Value [Member] \| Level 1
Assets
Mortgage loans	0	0
Policy loans	0	0
Real estate joint ventures	0	0
Other limited partnership interests	0	0
Other invested assets	172	322
Premiums, reinsurance and other receivables	0	0
Other assets	0	0
Liabilities
PABs	0	0
Long-term debt	0	0
Collateral financing arrangements	0	0
Junior subordinated debt securities	0	0
Other liabilities	0	0
Separate account liabilities	0	0
Estimated Fair Value [Member] \| Level 2
Assets
Mortgage loans	0	0
Policy loans	1,647	1,694
Real estate joint ventures	0	0
Other limited partnership interests	0	0
Other invested assets	70	163
Premiums, reinsurance and other receivables	713	728
Other assets	175	210
Liabilities
PABs	0	0
Long-term debt	18,357	18,564
Collateral financing arrangements	0	0
Junior subordinated debt securities	4,173	3,789
Other liabilities	1,223	948
Separate account liabilities	116,665	117,562
Estimated Fair Value [Member] \| Level 3
Assets
Mortgage loans	62,554	57,924
Policy loans	12,287	11,512
Real estate joint ventures	139	169
Other limited partnership interests	906	1,109
Other invested assets	320	359
Premiums, reinsurance and other receivables	2,444	2,382
Other assets	68	142
Liabilities
PABs	139,359	144,631
Long-term debt	0	0
Collateral financing arrangements	3,961	3,984
Junior subordinated debt securities	0	0
Other liabilities	1,323	1,292
Separate account liabilities	0	0
Carrying Value
Assets
Mortgage loans	59,530	55,770
Policy loans	11,618	11,764
Real estate joint ventures	67	102
Other limited partnership interests	704	950
Other invested assets	562	844
Premiums, reinsurance and other receivables	3,070	3,116
Other assets	251	324
Liabilities
PABs	134,219	139,735
Long-term debt	16,128	17,170
Collateral financing arrangements	4,196	4,196
Junior subordinated debt securities	3,193	3,193
Other liabilities	2,544	2,239
Separate account liabilities	$ 116,665	$ 117,562

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

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- Definition

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

+ References

No definition available.

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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.

+ References

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- Definition

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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No definition available.

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- Definition

The book value of investments in real estate joint ventures including direct and indirect investments.

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- Definition

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 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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-Glossary Separate Account

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