Investments (PCI Investments Acquired) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
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)	2,220	947
Cash flows expected to be collected	1,951	745
Fair value of investments acquired	$ 1,439	$ 503

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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
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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.

+ References

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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.

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