Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Available-for-sale securities, at fair value:
Fixed maturity securities (amortized cost)	$ 74,078	$ 72,718
Variable interest entities' fixed maturity securities (amortized cost)	679	677
Equity securities (cost)	$ 131	$ 137
Stockholders Equity
Preferred stock - shares authorized (in shares)	10,000,000	10,000,000
Series A preferred stock - shares issued (in shares)	9,532	9,532
Series A preferred stock - shares outstanding (in shares)	9,532	9,532
Common stock - shares authorized (in shares)	800,000,000	800,000,000
Common stock - shares issued (in shares)	268,457,558	271,402,586
Common stock - shares outstanding (in shares)	268,457,558	271,402,586