Investments (Consolidated Variable Interest Entities) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Assets:
Mortgage loans (commercial mortgage loans)	$ 6,120	$ 5,839
Accrued investment income relating to variable interest entities	526	501
Liabilities
Long-term debt, at estimated fair value, relating to variable interest entities	921us-gaap_LongTermDebt	928us-gaap_LongTermDebt
Other liabilities relating to variable interest entities	9,828us-gaap_OtherLiabilities	7,944us-gaap_OtherLiabilities
Consolidated securitization entities [Member]
Assets:
Mortgage loans (commercial mortgage loans)	272	280
Accrued investment income relating to variable interest entities	1	2
Total assets	273	282
Liabilities
Long-term debt, at estimated fair value, relating to variable interest entities	132	139
Other liabilities relating to variable interest entities	1	1
Total liabilities	$ 133	$ 140

Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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The aggregate carrying amount, as of the balance sheet date, of liabilities not separately disclosed in the balance sheet.

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The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

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