Consolidated Statement Of Comprehensive Income (Loss) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Disclosure Consolidated Statement Of Comprehensive Income Loss [Abstract]
Net income (loss)	$ (178)	$ 581	$ (14)	$ 591
Unrealized gains (losses) on available-for-sale securities: [Abstract]
Unrealized gains (losses) arising during the period	(153)	139	(140)	186
Provision (benefit) for income taxes	(53)	54	(49)	60
Total	(100)	85	(91)	126
Reclassification adjustments for (gains) losses included in net income (loss)	6	(43)	(19)	92
Provision (benefit) for income taxes	2	(15)	(7)	32
Total	4	(28)	(12)	60
Available-for-sale securities with other-than-temporary impairments:
Other-than-temporary impairments and unrealized gains (losses) arising during the period	2	(2)	7	9
Provision (benefit) for income taxes	2	(1)	4	3
Total	0	(1)	3	6
Reclassification adjustments for gains (losses) included in net income (loss)	(4)	9	(4)	50
Provision (benefit) for income taxes	(1)	3	(1)	18
Total	(3)	6	(3)	32
Foreign currency translation: [Abstract]
Net foreign currency translation gains (losses)	4	0	(39)	(11)
Provision (benefit) for income taxes	0	0	0	1
Total	4	0	(39)	(12)
Total other comprehensive income (loss)	(95)	62	(142)	212
Comprehensive income (loss)	$ (273)	$ 643	$ (156)	$ 803

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The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.