Derivatives (Fair Value Hedges) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivative Gains (Losses) Recognized for Derivatives	$ 57	$ (981)	$ (135)
Net Derivative Gains (Losses) Recognized for Hedged Items	(79)	992	127
Ineffectiveness Recognized in Net Derivative Gains (Losses)	(22)	11	(8)
Interest rate swaps \| Fixed Maturity Securities
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivative Gains (Losses) Recognized for Derivatives	5	42	(4)
Net Derivative Gains (Losses) Recognized for Hedged Items	(1)	(43)	0
Ineffectiveness Recognized in Net Derivative Gains (Losses)	4	(1)	(4)
Interest rate swaps \| Policyholder account balances [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivative Gains (Losses) Recognized for Derivatives	681	(830)	(82)
Net Derivative Gains (Losses) Recognized for Hedged Items	(667)	835	96
Ineffectiveness Recognized in Net Derivative Gains (Losses)	14	5	14
Foreign currency swaps \| Foreign-denominated fixed maturity securities
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivative Gains (Losses) Recognized for Derivatives	13	13	(1)
Net Derivative Gains (Losses) Recognized for Hedged Items	(11)	(12)	1
Ineffectiveness Recognized in Net Derivative Gains (Losses)	2	1	0
Foreign currency swaps \| Foreign-denominated policyholder account balances [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivative Gains (Losses) Recognized for Derivatives	(283)	(97)	3
Net Derivative Gains (Losses) Recognized for Hedged Items	270	110	(20)
Ineffectiveness Recognized in Net Derivative Gains (Losses)	(13)	13	(17)
Foreign currency forwards \| Foreign-denominated fixed maturity securities
Derivative Instruments, Gain (Loss) [Line Items]
Net Derivative Gains (Losses) Recognized for Derivatives	(359)	(109)	(51)
Net Derivative Gains (Losses) Recognized for Hedged Items	330	102	50
Ineffectiveness Recognized in Net Derivative Gains (Losses)	$ (29)	$ (7)	$ (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

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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

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

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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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