Investments (Details Textuals) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Summary of Certain Fixed Maturity Securities
Available-for-sale Securities, Debt Securities	$ 374,266	$ 350,271
Gross Unrealized OTTI Loss	361	724	601
Foreign corporate securities [Member]
Summary of Certain Fixed Maturity Securities
Available-for-sale Securities, Debt Securities	67,184	64,018
Net unrealized gains (losses)	5,654	3,789
Gross Unrealized OTTI Loss	(1)	1
Non-income producing fixed maturity securities [Member]
Summary of Certain Fixed Maturity Securities
Available-for-sale Securities, Debt Securities	85	62
Net unrealized gains (losses)	$ 11	$ (19)

Amount of debt securities categorized neither as held-to-maturity nor trading.

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