Basis of Presentation and Accounting Policies (Change in Non-credit Impairments Recognized in OCI) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Organization, Consolidation and Presentation of Financial Statements [Abstract]
OTTI losses recognized in OCI	$ (40)	$ (89)	$ (418)
Changes in fair value and/or sales	147	112	647
Tax and deferred acquisition costs	(55)	(14)	(113)
Change in non-credit impairments recognized in OCI	$ 52	$ 9	$ 116

Net of tax amount of other than temporary impairment (OTTI) on a debt security, categorized as available-for-sale or held-to-maturity, recognized in other comprehensive income (loss), attributable to the parent entity.

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

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 15D

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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