Investments (PCI Investments Acquired) (Details) (Fixed maturity securities, USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Fixed maturity securities
Purchased credit impaired investments as of their respective acquisition dates
Contractually required payments (including interest)	$ 820	$ 1,612
Cash flows expected to be collected	644	1,248
Fair value of investments acquired	$ 433	$ 841

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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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

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

+ Details

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- Definition

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.

+ References

+ Details

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- Definition

Amount of contractually required payments receivable at acquisition of acquired loans accounted for as available-for-sale debt securities with evidence of deterioration of credit quality.

+ References

+ Details

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