Investments and Derivative Instruments (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013		Jan. 31, 2013	Mar. 31, 2012
Other-Than-Temporary Impairment Losses
Balance as of beginning of period	$ (906)				$ (552)	$ (1,013)
Additions for credit impairments recognized on securities not previously impaired	(7)	[1]	(8)	[1]
Additions for credit impairments recognized on securities previously impaired	(11)	[1]	(2)	[1]
Securities that matured or were sold during the period	33		114
Securities due to an increase in expected cash flows	6		3
Balance as of end of period	$ (531)				$ (552)	$ (1,013)

[1] These additions are included in the net OTTI losses recognized in earnings in the Condensed Consolidated Statements of Operations.