Derivatives (Fair Value Hedges) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivative Gains (Losses) Recognized for Derivatives	$ (64)	$ 189
Net Derivative Gains (Losses) Recognized for Hedged Items	62	(176)
Ineffectiveness Recognized in Net Derivative Gains (Losses)	(2)	13
Interest rate swaps \| Fixed Maturity Securities
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivative Gains (Losses) Recognized for Derivatives	(5)	1
Net Derivative Gains (Losses) Recognized for Hedged Items	7	1
Ineffectiveness Recognized in Net Derivative Gains (Losses)	2	2
Interest rate swaps \| Policyholder account balances [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivative Gains (Losses) Recognized for Derivatives	197	209
Net Derivative Gains (Losses) Recognized for Hedged Items	(198)	(204)
Ineffectiveness Recognized in Net Derivative Gains (Losses)	(1)	5
Foreign currency swaps \| Foreign-denominated fixed maturity securities
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivative Gains (Losses) Recognized for Derivatives	10	(4)
Net Derivative Gains (Losses) Recognized for Hedged Items	(8)	4
Ineffectiveness Recognized in Net Derivative Gains (Losses)	2	0
Foreign currency swaps \| Foreign-denominated policyholder account balances [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivative Gains (Losses) Recognized for Derivatives	(249)	(27)
Net Derivative Gains (Losses) Recognized for Hedged Items	245	32
Ineffectiveness Recognized in Net Derivative Gains (Losses)	(4)	5
Foreign currency forwards \| Foreign-denominated fixed maturity securities
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivative Gains (Losses) Recognized for Derivatives	(17)	10
Net Derivative Gains (Losses) Recognized for Hedged Items	16	(9)
Ineffectiveness Recognized in Net Derivative Gains (Losses)	$ (1)	$ 1

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5618551-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

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-Subparagraph (a),(c),(d),(e)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

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Amount of gain (loss)recognized in the income statement from the hedging ineffectiveness of a fair value hedge.

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