Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Fixed maturity securities, available-for-sale, at fair value	$ 10,242	$ 9,972
Common stock par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	500,000,000	500,000,000
Common stock, shares issued (in shares)	142,919,399	158,306,661
Common stock, shares outstanding (in shares)	142,919,399	158,306,661
Accumulated other comprehensive income, tax provision	$ 113	$ 159
Deferred equity compensation (in shares)	320,193	320,193