Derivatives (Net Derivative Gains Losses) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Components of Net Derivatives Gains (Losses)
Derivatives and hedging gains (losses)	$ 848met_DerivativesAndHedgingGainslosses	$ 452met_DerivativesAndHedgingGainslosses
Embedded derivatives gains (losses)	(27)	(109)
Total net derivative gains (losses)	$ 821	$ 343

This caption represents the net unrealized and realized gains (losses) on derivatives and hedged items recognized during the reporting period.

No definition available.

+ Details

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- Definition

Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

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

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- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ 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

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