Investments (PCI Investments Acquired) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Mortgage Loans
Purchased credit impaired investments as of their respective acquisition dates
Contractually required payments (including interest)	$ 0	$ 0
Cash flows expected to be collected	0	0
Fair value of investments acquired	0	0
Fixed Maturity Securities
Purchased credit impaired investments as of their respective acquisition dates
Contractually required payments (including interest)	947	1,872
Cash flows expected to be collected	745	1,446
Fair value of investments acquired	$ 503	$ 978

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Fair value at acquisition of acquired loans accounted for as available-for-sale debt securities with evidence of deterioration of credit quality.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 15

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

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-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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Amount of cash flows expected to be collected at acquisition of acquired loans accounted for as available-for-sale debt securities with evidence of deterioration of credit quality.

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Fair value at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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