Investments and Derivative Instruments Level 4 Fair Value Hedges (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Derivatives, Fair Value [Line Items]
Loss on Fair Value Hedge Ineffectiveness	1
JAPAN \| Fair Value Hedging [Member] \| Three Win Related Foreign Currency Swaps [Member]
Derivatives, Fair Value [Line Items]
Change in Unrealized Gain (Loss) on Hedged Item in Foreign Currency Fair Value Hedge	$ (44)	$ 0

Amount of the increase (decrease) in fair value of the hedged item in a foreign currency fair value hedge which was recognized in earnings, net of offsets by the gain (loss) on the hedging instrument to the extent that the fair value hedge was determined to be effective.

No definition available.

Name:	us-gaap_ChangeInUnrealizedGainLossOnHedgedItemInForeignCurrencyFairValueHedge1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration