Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Available-for-sale securities, at fair value:
Fixed maturity securities (amortized cost)	$ 81,993	$ 78,609
Variable interest entities' fixed maturity securities (amortized cost)	596	587
Equity securities (cost)	$ 226	$ 216
Stockholders Equity
Preferred stock - shares authorized (in shares)	10,000,000	10,000,000
Common stock - shares authorized (in shares)	800,000,000	800,000,000
Common stock - shares issued (in shares)	243,835,893	256,551,440
Common stock - shares outstanding (in shares)	243,835,893	256,551,440
Series A Preferred Stock [Member]
Stockholders Equity
Series A preferred stock - shares outstanding (in shares)